Taxes
Filing, withholding, quarterly estimates — Form 1040 line by line.
US federal tax filing for W-2 employees, 1099 contractors, and the gig economy. Form 1040 mechanics, quarterly estimated taxes, standard versus itemized deduction math, and the credits and deductions worth knowing before tax season.
The US federal tax system is large, dense in jargon, and surrounded by paid-tax-prep marketing that overstates the complexity for the typical case. For a substantial majority of US households — single W-2 wage earners with no dependents, married couples with combined W-2 income and no complicated investments, retirees on Social Security plus modest investment income — the actual annual tax return takes thirty to sixty minutes to complete and costs nothing if filed through one of the federally-supported free options. The fear of the IRS is much larger than the actual annual task for most households.
This section covers the practical mechanics of filing US federal taxes: how Form 1040 actually works, the difference between W-2 and 1099 income and the additional paperwork that 1099 income requires, the standard versus itemized deduction decision (the standard wins for over 90% of US filers since the 2017 tax law), the credits and deductions worth knowing before tax season, the quarterly estimated tax system that self-employed workers and substantial-investment-income filers need to navigate, and the free-filing pathways the IRS, state revenue departments, and certain nonprofit programs make available at no cost.
Two structural facts anchor every guide in this section. First, the federal income tax is a pay-as-you-go system. Withholding on W-2 paychecks (or quarterly estimated payments for 1099 income) is the prepayment toward annual tax liability. The annual return is the reconciliation — a refund means you over-prepaid, a balance owed means you under-prepaid. Large refunds are not free money; they are your own money returned because too much was held back during the year. Adjusting W-4 withholding to land closer to neutral keeps the cash in your hand throughout the year rather than as a lump sum in April. Second, the IRS supports several free filing pathways. The IRS Free File program (for adjusted gross income of $89,000 or less), the Volunteer Income Tax Assistance program (free in-person help for moderate-income filers), and Free Fillable Forms (for higher-income filers comfortable doing the math themselves) cover the vast majority of typical filing situations. The paid products (TurboTax, H&R Block at retail, professional preparers) are appropriate for genuinely complex returns but unnecessary for the typical W-2 employee.
What this section will not do is publish state-by-state filing guides (50 separate state tax systems is more than we can responsibly cover) or specific tax-advice recommendations for individual returns. Filing position, deduction eligibility, credit qualification, and entity choice depend on facts specific to each filer's situation that a published guide cannot address. The guides explain the federal system in general; for decisions on a specific return, an enrolled agent, CPA, or attorney is the right resource.
All articles in the taxes hub are written and edited by Cristian Corrales. Quantitative claims are anchored to primary US sources (CFPB, FDIC, FRB, IRS, FICO, FINRA, SEC, NCUA). Where the subject benefits from licensed review, a named US CFP, CPA, or attorney reviews before publication — editorial policy.
Start here
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Filing US taxes for the first time — Form 1040 line by line
How to file a federal tax return as a first-timer: W-2 vs 1099, standard vs itemized, refund mechanics, deadlines, free filing options.
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AGI on Form 1040 — line by line, with Schedule 1 in plain English
Every income line (1a–8) and every Schedule 1 adjustment that brings total income down to AGI on line 11 — the figure most credit and deduction phase-outs actually test against.
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Schedule SE — the 15.3% self-employment tax explained line by line
How Schedule SE actually computes the tax, where the deductions sit, the Social Security wage base ceiling, and the additional Medicare surcharge.
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Form W-4 — the withholding math that prevents April surprises
The 5 steps mapped to actual brackets, why dual-earner default under-withholds, and how to dial the W-4 to within $500 of zero at filing time.
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S-corp election for the self-employed — when the SE tax math works
How the salary + distribution split cuts the 15.3% SE tax, the reasonable-salary IRS standard, two worked examples ($150K consultant, $80K freelancer), and the QBI interaction.
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FICA payroll taxes — Social Security, Medicare, and the surtaxes above
The 6.2% OASDI portion up to the wage base, the 1.45% Medicare uncapped, the 0.9% Additional Medicare above ACA thresholds, and the self-employed SECA equivalent.
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Section 199A QBI deduction after OBBBA — the 20% pass-through math
How the qualified business income deduction works now that OBBBA made it permanent: the 20% math, the new $400 minimum, the 2026 thresholds, the W-2 wage limit, and the SSTB phase-out.
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MAGI — the number behind every tax phase-out
How modified adjusted gross income works: each MAGI variant, the add-backs that differ by provision, and the levers that move it.
Browse by theme
91 pieces, grouped by the part of the return they touch. Jump straight to the family you need.
Income documents, box by box
What each box on a W-2, 1099 or 1098 actually means, and the Form 1040 line it lands on.
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Your W-2 doesn't show AGI — how to build line 11 from it
Box 1 is taxable wages, not adjusted gross income. The W-2-to-Form-1040 walkthrough: line 9, the Schedule 1 adjustments, and a worked example landing on line 11.
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W-2 Box 12 codes, A to II — what each one means on your 1040
Every Box 12 code from the official 2026 IRS instructions, including the new TP and TT codes for tips and overtime — and which ones actually change your return.
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When your 1098-T box 5 exceeds box 1 — how much is taxable
Box 5 minus box 1 is not your taxable scholarship. The Pub 970 Worksheet 1-1 walkthrough, why room and board breaks the gap, and the American Opportunity Credit trade-off.
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2027-28 FAFSA — which 2025 Form 1040 lines feed your Student Aid Index
The form opened on September 23, 2026 and imports line 11, line 24 and five adjusting lines from your 2025 return. The full mapping, the SAI worksheet on a worked family of four, and why a 401(k) deferral lowers the index but a deductible IRA does not.
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Schedule 1-A 2026 draft — every line that changed from 2025
Per-employer tip and overtime tables keyed to W-2 box 12 codes TP and TT, three new 1099 boxes, the Form 1098-VLI car-loan line, a senior cutoff of January 2, 1962 and a total that moves to Form 1040 line 13a. Four examples recalculated line by line.
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Form 1098-VLI box by box — the car loan interest form for 2026
The lender form behind the car loan interest deduction, finalized by T.D. 10054: every box, the VIN and original-use checks, the $10,000 cap with its $200-per-$1,000 phase-out, and the simpler 2025 transition statement it replaces.
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Form 1040 2026 draft — every line that changed from 2025
A new work-authorization question, line 12f for non-itemizer charity (up to $1,000 or $2,000 joint, no 0.5% floor), lines 13a and 13b swapped, 24a to 24c for the Form 1062 farmland installment and 32a to 32c for Schedule 3-A. AGI stays on line 11a.
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Form 5695 for 2026 — only the solar credit carryforward is left
The 2026 draft is four lines: the unused residential clean energy credit from line 16 of the 2025 form, a tax-liability cap, and the remainder carried to 2027. Installations completed after December 31, 2025 get nothing.
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Form 1099-LPS and the $2,600 long-term care 401(k) withdrawal
SECURE 2.0 lets plans pay long-term care premiums with no 10% penalty: the least of premiums, 10% of the vested balance or $2,600 ($2,700 in 2027). Optional for plans, taxable, and reported on a new 1099.
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Schedule A 2026 draft — every itemized-deduction line that changed
SALT cap $40,400 with the phase-down at $505,000, mortgage insurance premiums back on line 8d, a charity floor worksheet at 0.5% of AGI, gambling losses at 90%, educator expenses on 17k, and the $384,350 question that triggers the new 2/37 limitation of section 68. Worked examples for each.
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Charitable deduction 2026 — $2,000 without itemizing, and a 0.5% floor
Non-itemizers can deduct up to $1,000 or $2,000 of cash gifts (not donor-advised funds), while itemizers lose the first 0.5% of AGI. A couple for whom the two rules flip the choice by $100, and what bunching is now worth.
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Form 6251 2026 draft — the AMT exemption now phases out at $500,000
Exemption $90,100 single and $140,200 joint, a phase-out that starts at $500,000 / $1,000,000 and runs at 50 cents per dollar, a 42% marginal zone, why the senior deduction is added back on line 1a, an ISO exercise worked line by line and the projected 2027 figures.
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Trump account gifts and Form 709 — the Rev. Proc. 2026-25 safe harbor
Why a contribution to a Trump account opened for a child looks like a future-interest gift, the five conditions under which the IRS lets you skip the gift tax return, and the all-or-nothing trap: gift splitting, a 529 five-year election or one gift over $19,000 puts every contribution back on Form 709.
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Form 1099-NEC for 2026 — the $2,000 threshold and the new boxes
Payments made from 2026 are reported only at $2,000 or more, the redesigned form adds cash tips, tipped-occupation codes and overtime in boxes 1b to 1d, and the inflation clause in the statute puts the 2027 threshold at $2,100.
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TTOC list — all 71 Treasury tipped occupation codes
The three-digit codes from T.D. 10044 that employers and payers print on 2026 W-2s and 1099s for the no-tax-on-tips deduction, grouped in the eight categories of the rule, plus what code 000 means for tips earned outside the list.
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Form 4547 line by line — the Trump account election and the $1,000 deposit
The December 2025 form, part by part: who can elect, the pilot-program deposit for children born 2025 through 2028, the three ways to file (including the IRS online account since May 28, 2026) and the deadline in the proposed regulations.
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Schedule 3-A 2026 — the new federal public benefit form, line by line
The draft form behind proposed rule REG-119882-25: how lines 1a to 8 isolate the refunded portion of the EIC, ACTC, AOTC and adoption credit, who is a qualified alien under 8 U.S.C. 1641(b), and the comment deadline of October 5, 2026.
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Form 1099-INT box by box — where each box lands on your return
Box 1 and box 3 both become taxable interest, but box 3 Treasury interest is exempt from state tax; box 2 is a separate Schedule 1 deduction; box 8 never touches Schedule B. The full routing map.
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1099-DIV box 1a vs 1b vs 2a — ordinary, qualified, capital gains
Box 1b is a slice of box 1a, never an addition to it; box 2a is a separate bucket of long-term gain that can skip Schedule D for Form 1040 line 7. The three-number relationship, decoded.
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Form 1099-B to Form 8949 — covered, noncovered, and Box A–F
How the box 12 basis-reported check plus the holding period decide which of the six Form 8949 category boxes a sale lands in, and when you override the broker's basis.
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Form 1099-DA for 2026 — box by box, and the first year of basis
Digital asset sales reported on their own form: 2026 is the first year basis appears, only for assets bought in a custodial account after 2025, with no backup withholding yet and the matching Form 8949 boxes.
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Selling a T-bill early — how §1271 splits the gain on your 1099-B
Box 1f on a T-bill sold before maturity is not a broker error: §1271's day-count formula turns part of the gain into ordinary interest, with code D on Form 8949 and a state-tax exemption to claim.
Investments, capital gains and the 3.8% surtax
Where a brokerage year ends up on the return: Form 8949 categories, Schedule B and D triggers, and the net investment income tax.
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Form 8949 column (f) codes — the adjustment-code cheat sheet
Every column (f) adjustment code in plain English, the column (g) sign rule that trips up investors, and a worked wash-sale (code W) example. The form mechanics, not the rates.
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W-2 box 12 code V — fix the cost basis the broker got wrong
Code V is the stock-option spread already taxed in box 1, yet the 1099-B leaves it out and overstates your gain. The Form 8949 fix: code B in column (f) and a negative column (g) adjustment.
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When is Schedule B required? The $1,500 rule and seven more
You file when taxable interest or ordinary dividends top $1,500 — each tested separately — plus seven other triggers, including nominee income, the savings-bond exclusion, and the foreign-account question.
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Schedule D Tax Worksheet — when lines 18 and 19 take over
An amount on Schedule D line 18 or 19 swaps the friendly 0/15/20 worksheet for the long one. Collectibles, QSBS, and depreciated real estate — and why the 25% and 28% rates are ceilings, not flat charges.
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Form 8960 line by line — the 3.8% net investment income tax
The 3.8% surtax hits the smaller of net investment income or MAGI over the $200k/$250k/$125k non-indexed thresholds. What counts, what does not, and the line-by-line flow.
Deductions and credits
The standard-versus-itemized decision, the pass-through deduction, and the retirement credits that survive into the Saver’s Match era.
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Standard deduction vs itemizing — when the math tilts each way
The mechanics, the SALT cap, the itemizing thresholds, and worked examples for both. Post-TCJA, ~90% take standard — here is when itemizing still wins.
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Form 8995 — the simplified QBI deduction, line by line
The one-page route to the 20% pass-through deduction when 2026 taxable income is at or below $201,750 single / $403,500 MFJ. The lesser-of computation, the capital-gains ceiling, and the OBBBA $400 floor.
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Form 2441 in 2026 — the 50% credit and the line 8 phase-down table
The full 2026 line 8 table from the draft instructions: 50% down to 35% by $43,000, a plateau to $150,000 joint or $75,000 otherwise, the 20% floor at $206,000 or $103,000, the $7,500 dependent care FSA cap, and three families worked 2025 against 2026.
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Form 8880 line 4 — the distribution that can erase your Saver's Credit
The testing-period distributions that reduce the credit, the exceptions that do not count, and why line 4 matters most in the final years before the 2027 Saver's Match.
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The Saver's Match replaces the Saver's Credit in 2027
From 2027, SECURE 2.0 turns the Saver's Credit into a 50% federal match deposited straight into your retirement account — up to $1,000. The statutory income bands.
Estimated taxes, extensions and penalties
Safe harbors, the two Form 2210 routes, and what an October extension does and does not buy you.
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The estimated-tax safe harbor — how much to pay to skip the penalty
Pay 90% of this year or 100% of last year (110% above $150K AGI) and the underpayment penalty cannot touch you, whatever the final bill. With a worked example.
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Form 2210 Schedule AI — annualize income to kill the penalty
The default penalty assumes even income. Schedule AI matches each installment to when you actually earned it, with the fixed 4/2.4/1.5/1 multipliers and the all-or-nothing trap.
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How the Form 2210 underpayment penalty is actually calculated
The estimated-tax penalty is quarterly interest, not a flat fine: the 2026 rates, the $1,000 floor, the 90/100/110 safe harbors, and why the timing of each payment matters.
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How to file a tax extension — Form 4868 and the Oct 15 date
Form 4868 buys six months to file, to October 15 — but not to pay. The failure-to-file penalty is ten times the failure-to-pay penalty, so always file on time even when you cannot pay. A worked $5,000 example across three choices.
Health accounts and coverage
HSAs, FSAs, the HDHP gate and the premium tax credit — the pre-tax health side of the return.
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HSA vs FSA — which pre-tax health account is yours
One is portable, invests, and rolls over; the other is the employer's and expires. The 2026 limits, the HDHP gate, and the Limited-Purpose FSA combo that runs both.
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HDHP vs PPO — the premium-deductible math, with HSA
How to compare an HDHP against a PPO: premium savings, deductible risk, out-of-pocket caps, and the HSA tax advantage that tilts the math.
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HSA for the self-employed — the deduction works, the FICA break doesn't
No employer needed: the above-the-line deduction and the 2026 limits stand. What changes is FICA — payroll contributions skip the 7.65%, yours don't. The honest math, worked.
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Form 8889 line by line — the HSA deduction without the line-9 trap
Why W-2 box 12 code W goes on line 9 not line 2, the 2025 contribution limits, the per-person catch-up, and the path down to the deduction on Schedule 1, line 13.
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The HSA last-month rule and its 13-month testing-period trap
Fund the full year limit even if eligible only part of the year — but a lapse before December 31 of the next year claws it back with a 10% tax. The dates, the math, and the prorate opt-out.
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2027 ACA subsidy table — Rev. Proc. 2026-26 and the 400% cliff
The IRS table for 2027 coverage runs 2.15% to 10.22% of income and stops at 400% of the poverty line: the cliff in dollars by household size, a worked example, repayment without a cap, and the two different 2027 required contribution percentages.
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Form 8962 line 5 — your percentage of the poverty line
The line says drop the decimals, not round, so 399.9% becomes 399. Why that one digit now flips your premium tax credit to zero in 2026, after the enhanced-subsidy cliff returned.
Retirement accounts and distributions
Basis, rollovers, missed RMDs and the ways money leaves an IRA without the usual tax bill.
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Form 5498 — why it arrives in May and what to do with it
The IRA information form that shows up after the filing deadline by design. Box by box: contributions, rollovers, conversions, year-end value, and when to actually act.
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Form 8606 line 14 — when you have lost track of your IRA basis
The basis carryforward chain from line 14 to next year's line 2, how to reconstruct lost basis from Form 5498 and IRS transcripts, and the $50 penalty you can usually waive.
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Form 5329 — missed your RMD? Cut the penalty to 10% or zero
SECURE 2.0 dropped the missed-RMD excise from 50% to 25%, and to 10% if you correct it inside the window. The Part IX mechanics and the reasonable-cause RC waiver that can erase it entirely.
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Form 8915-F — disaster distributions and the 3-year spread
Up to $22,000 per disaster, no 10% penalty, income split over three years, and a 3-year-and-1-day window to repay and claw the tax back. Why the $100,000 figure people remember belongs to 2020 CARES.
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QCDs — give from your IRA, skip the tax entirely
From age 70½, up to $111,000 a year (2026) can travel from an IRA straight to charity without touching your AGI — stronger than a deduction, and from 73 it satisfies the RMD.
Family, gifts and one-off income
Situations that show up once and rarely twice: a child’s investment income, a split gift, canceled debt, caregiver payments.
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The kiddie tax — when a child's income is taxed at your rate
In 2026 a child's unearned income above $2,700 is taxed at the parent's marginal rate on Form 8615. The three-tier thresholds, a worked $4,000 example, and the custodial-Roth and 529 levers that defuse it.
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Do both spouses file Form 709 when splitting a gift?
Usually yes, but two narrow exceptions let only the giver file while the other consents. The 2026 $19,000/$38,000 thresholds, the three scenarios, and the Notice of Consent.
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A 1099-C after a charge-off — when canceled debt is not taxed
A 1099-C is not an automatic tax bill. The insolvency exclusion on Form 982 line 1b often zeroes it out — the smaller-of rule, a worked insolvency worksheet, and the 36-month myth the IRS removed in 2016.
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Medicaid waiver payments (Notice 2014-7) — the new reporting path
Tax-free under Notice 2014-7, but the mechanic changed: W-2 box 1 to line 1a, box 12 code II to line 1d, and a negative on Schedule 1 line 8s. Plus the Earned Income Credit choice.
The 2027 numbers, tracked
Every limit and bracket for 2027 — the ones the IRS has already published, and the ones we project from the statutory formula until it does.
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IRS 2027 inflation adjustments tracker — what the CPI has decided
One page for every indexed 2027 number: the statutory 12-month window closed with the August CPI on September 11, the C-CPI-U math that reproduces 2026 exactly, and what that print decided, with the missing October 2025 month shown both ways.
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2027 tax brackets and standard deduction — the projection
The 2026 brackets and standard deduction are confirmed; how the 2027 figures are projected by chained-CPI indexing, clearly labeled, pending the IRS October release.
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The 2027 401(k) and IRA limit projection — the statutory math
Applying the formula in 26 U.S.C. 402(g)(4) to CPI data: $25,000 or $25,500 for the 401(k), $8,000 for the IRA — and the exact summer CPI threshold that decides it.
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2027 Roth IRA and IRA deduction phase-outs — the formula, closed
The phase-out ranges run on the tax-bracket window, not the Q3 one, so the August CPI closed them: $158,000 to $173,000 single, $250,000 to $260,000 joint (or $249,000 to $259,000 if October 2025 is imputed), $83,000 to $93,000 and $133,000 to $153,000 for the deduction. Control against 2026: four for four.
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2027 capital gains brackets — the 0% band clears $100,000
The 0% and 15% thresholds are indexed on the tax-bracket window, so the August CPI settled them: $102,100 and $633,600 joint, $51,050 and $563,200 single, a worked gain-harvesting example, and why the NIIT line does not move.
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2027 foreign earned income exclusion and the 2026 draft Form 2555
The exclusion projects to $137,300 (or $137,100 if October 2025 is imputed), only $8.80 above its rounding step; housing base and cap, the stacking rule, and what changed on the 2026 draft Form 2555.
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The 2027 transit and parking benefit limit is already $350
The commuter benefit cap under section 132(f) rounds to $350 a month either way the missing October month is treated, which matters for open-enrollment elections: the worked savings math and why the bicycle benefit is gone for good.
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Gift tax annual exclusion 2027 — $20,000, up from $19,000
The first increase since 2025: the exclusion clears $20,000 by $119, gift splitting reaches $40,000 per recipient, five-year 529 front-loading $100,000, and the non-citizen spouse figure depends on October.
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SALT cap 2027 — $40,804, phase-down from $510,050
No CPI needed: the statute sets 2027 at 101 percent of 2026. The worksheet line by line, the $10,000 floor reached at $612,730 of MAGI, the married-filing-separately math, and the return to $10,000 in 2030.
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QBI deduction 2027 — thresholds and the $400 minimum, projected
The section 199A thresholds project to $208,300 single and $416,600 joint (or $208,050 and $416,100 if October is imputed), and the new minimum deduction to $410 or $415 with $1,030 of active QBI.
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The 2027 QCD limit is already $114,000
Printed in the same November notice as the 401(k) limit but indexed on the tax-bracket window, so the August CPI settled it: $114,000 a year and $57,000 for the one-time split-interest gift, six for six against 2024-2026, with a worked 2026 example worth $2,112.
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Child tax credit 2027 — $2,300 per child, $1,800 refundable
The 2025 law indexes the $2,200 credit with its increase rounded down to $100, and the August CPI pushes it over the step: $2,300 and $1,800 for 2027, against the official $2,200 and $1,700 for 2026, plus the 2026 draft Schedule 8812 line by line.
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Federal scholarship tax credit 2027 — $3,400 joint and Form 8525
The October 2026 proposed rules treat spouses as separate taxpayers for the $1,700 cap, let donors in any state give to a listed SGO, and apply state credits first to any amount not designated as qualified.
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ABLE limits 2027 — $20,000, and the Saver's Credit that survives
The ABLE cap moved to its own 1996 base in 2026 and stays at $20,000 in 2027, ABLE to Work adds up to $15,960, and from 2027 the Saver's Credit applies only to a beneficiary's own ABLE contributions, on up to $2,100.
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EITC 2027 — the projected earned income credit table
The official 2026 table for returns filed in early 2027, and the 2027 table projected from section 32(j) in two columns, because the missing October 2025 CPI moves most cells by $10 to $30: maximum $8,496 or $8,487 with three children.
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Adoption tax credit 2027 and the 2026 draft Form 8839
The credit reaches $18,250 or $18,220 in 2027 depending on the October method, with $5,280 refundable either way; the 2026 draft Form 8839 already carries $17,670, the $265,080 phase-out and the $5,120 refundable line.
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HSA contribution limits 2027 — official, per Rev. Proc. 2026-24
The IRS already set the 2027 HSA limits in May: $4,500 self-only, $9,000 family. The HDHP thresholds, the $1,000 catch-up that never changes, and the new DPCSA rule.
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The 2027 health FSA contribution limit projection
The 2026 health FSA limit is $3,400. With the August CPI in, the indexing math puts the 2027 cap at $3,500 and the carryover at $700, whichever way the IRS treats the missing October 2025 month.
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Dependent care FSA limit 2027 — still $7,500, no inflation bump
Section 129 has no inflation clause, so the 2027 exclusion stays at $7,500 ($3,750 married filing separately) while the health FSA cap moves to $3,500 — and how the FSA and the Form 2441 credit share the same expenses.
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Educational assistance limit 2027 — $5,250 becomes $5,400
The tax-free cap on employer tuition and student loan payments has not moved since 1986. The 2025 law indexes it from 2027, and the August CPI puts the first step at $150 either way the missing October reading resolves.
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2027 poverty guidelines — about $16,580 for one person, projected
HHS updates the Census thresholds by the calendar-year CPI-U, so September to December 2026 are still open: $16,580 plus $5,840 per person in the central case, $34,100 for four, reproduced four for four against 2023-2026.
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Roth catch-up wage threshold 2027 — already $155,000
The third-quarter CPI-U settles it before September is even published: $155,000 tested against 2026 FICA wages, and the age 60-63 super catch-up at $11,750, both checked against Notice 2025-67.
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Exit tax 2027 — the $218,000 test and the $940,000 exclusion
The covered expatriate tax test and the mark-to-market exclusion are indexed and rounded to the nearest $1,000, so October decides between $218,000 and $217,000; the $2,000,000 net worth test never moves.
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SIMPLE IRA limits 2027 — $17,500, or $19,100 at small employers
The standard deferral rises to $17,500 and the 110 percent limit for employers with 25 or fewer workers jumps $1,000 to $19,100, while the catch-ups hold at $4,000, $3,850 and $5,250 and the extra employer contribution reaches $5,400.
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Excess business loss limit 2027 — $264,000 ($528,000 joint)
Section 461(l) caps how much business loss you can deduct against other income: $264,000, or $528,000 on a joint return, already closed by the August index and well below the 2025 figure of $313,000 after the 2025 law reset the base year.
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QSEHRA limits 2027 — $6,700 self-only, projected
Section 9831(d) indexes the small-employer HRA from a 2015 base and rounds the amount down to $50: $6,700 self-only either way October resolves, $13,550 or $13,500 family, checked two for two against 2026.
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Long-term care premium deduction limits 2027 — already set
The age-based limits run on the August medical-care CPI, which is already published: $500, $940, $1,890, $5,030 and $6,290, plus a $440 per diem, reproduced six for six against 2026.
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Kiddie tax 2027 — the threshold rises to $2,800
The dependent standard deduction floor moves from $1,350 to $1,400, so unearned income above $2,800 is taxed at the parents' rate; Form 8814 runs from $1,400 to $14,000 and the child's AMT add-on reaches $10,050.
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Trust and estate tax brackets 2027 — 37% from $16,500
The Form 1041 brackets project to $3,400, $12,100 or $12,050, and $16,500, the NIIT threshold follows the top bracket, and the 2025 law gave the 10% bracket an extra year of inflation.
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Section 179 limit 2027 — $2,640,000, projected
The August CPI settles the 2027 dollar limitation at $2,640,000 either way the missing October 2025 reading resolves; the phase-out threshold lands at $4,220,000 or $4,230,000 and the SUV cap at $33,000 or $33,100, checked three for three against 2026.
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2027 IRMAA brackets — the Medicare surcharge projection
Your 2027 Medicare surcharge is set by your 2025 income via the two-year lookback. The confirmed 2026 brackets, the cliff, and a clearly labeled 2027 projection.
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The 2027 Social Security wage base projection
The 2026 wage base is $184,500; the Trustees project $190,200 for 2027 (wage-indexed). What the cap taxes, what it does not (Medicare), and when it is official.
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2027 estate and gift tax exemption — the projected numbers
OBBBA made the $15M per-person estate and gift exemption permanent from 2026, indexed from 2027. The projected 2027 figure, the $19,000 annual gift exclusion, and why the sunset never came.
What changed recently
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2027 401(k) & IRA contribution limits: projections vs 2026
With 2026 limits confirmed (401k $24,500, IRA $7,500), here are the 2027 401(k), IRA, and Roth projections and the IRS rounding math behind each one.
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Tax season prep — the year-round runway to file confidently
A month-by-month checklist for the months before tax-filing season opens — what to organize, verify, and plan so you file confidently and capture deductions.
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The 0% capital gains bracket — the planning lever most filers miss
For single filers under ~$49K and couples under ~$99K of taxable income, long-term capital gains are taxed at 0% federal. The structural mechanics.
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Vocabulary for this topic
- AGI (Adjusted Gross Income) Total income minus specific above-the-line deductions — the basis for most downstream credit and deduction phase-outs.
- MAGI (Modified Adjusted Gross Income) AGI plus a set of add-backs that varies by tax provision — the gating number for Roth contribution and several credits.
- Standard deduction The flat deduction from AGI ~90% of US households take instead of itemizing post-TCJA.
- SALT cap The $10,000 limit on combined state and local taxes deductible on Schedule A — the structural break on itemizing in high-tax states.
- Form 1040 The federal individual income tax return — the form every US filer uses.
- Additional Medicare Tax The 0.9% surtax on wages and SE income above filing-status thresholds — non-indexed since 2013.
- OASDI wage base The annual ceiling on wages subject to Social Security tax — $176,100 in 2025, adjusted yearly.
- NIIT The 3.8% net investment income surtax above $200K single / $250K joint MAGI — non-indexed since 2013.
- QBI deduction The up-to-20% pass-through deduction under Section 199A — made permanent by OBBBA, with a new $400 floor for 2026.
Frequently asked
Does finbarrow do my taxes for me?
No. finbarrow is editorial — we explain how the federal tax system works, what forms apply to which situations, and what free-filing options the IRS supports. The actual return is filed by you through one of the free options (IRS Free File guided software for adjusted gross income of $89,000 or less, or Free File Fillable Forms above that) or through a paid product or professional preparer if your situation warrants. Note that IRS Direct File, the file-directly-with-the-IRS pilot, was discontinued and is not available for the 2026 filing season. The guides walk through the choice.
Do I need to file if my income is below the standard deduction?
Generally no, but yes if you had federal income tax withheld from a W-2 paycheck and want the refund, if you qualify for refundable credits (Earned Income Tax Credit, Premium Tax Credit), or if you had self-employment income above $400. The filing thresholds are published by the IRS each year and depend on filing status and age. When in doubt, filing is the safer default because not filing forfeits any refund you would have received.
How do quarterly estimated taxes work if I have both W-2 and 1099 income?
The W-2 withholding counts toward your total tax liability for the year, and your quarterly estimated payments cover the gap on the 1099 portion. Many filers in this situation increase their W-2 withholding (via Form W-4) instead of making quarterly payments, which is administratively simpler — additional withholding is treated as paid evenly across the year and avoids any underpayment penalty regardless of when it actually went in. Whether to use W-4 adjustment or quarterly payments depends on whether you can predict your 1099 income early in the year.
Is finbarrow giving me tax advice?
No. Every article in this section is educational. Filing position, deduction eligibility, credit qualification, and entity choice depend on your specific financial situation, state of residence, and other facts. The guides explain how the federal system works in general; for decisions on your specific return, consult an enrolled agent, CPA, or attorney. For simple W-2 returns, the IRS-supported free filing options walk you through the questions one at a time without needing outside advice.
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Credit Cards
The math behind cash back, travel rewards, and 0% APR.
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Savings & CDs
Where your dollars actually earn — verified at the bank.
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Investing & Retirement
Roth IRA, 401(k), index funds — decisions you make once a decade.
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Loans & Mortgages
Auto, mortgage, personal, student — when refinancing actually pays.
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Credit & FICO
Build, fix, and optimize your credit — the 30% utilization rule is wrong.
Social Security, Medicare and payroll taxes
How benefits get taxed, how withholding works on them, and the surtaxes and refunds that come out of payroll.
Social Security tax thresholds — $25,000/$32,000, frozen since 1984
The thresholds that make Social Security taxable have never been indexed for inflation. The two-tier math of 26 U.S.C. 86, worked examples, and the tax torpedo.
W-4V vs W-4P — withholding on Social Security and pensions
Social Security withholding is a fixed menu of four rates on Form W-4V; pensions use Form W-4P and its steps. Which form covers which income, and where each one goes.
SSA-1099 lump-sum election — taxing Social Security back pay
A retroactive disability or retirement check crammed into one year can be taxed as if received across the prior years — no amended returns, just the Form 1040 line 6c election and Publication 915.
SSA-44 for a work stoppage — lower your IRMAA after retiring
A Medicare surcharge set by two-year-old income can be appealed when you retire. The fixed list of life-changing events, Step 2 vs Step 3, and the self-statement option.
Excess Social Security tax from two employers — Schedule 3 line 11
Two jobs can withhold past the annual cap. The refundable credit on Schedule 3 line 11, the 2024–2026 maximums, and why one employer over-withholding needs Form 843 instead.
Form 8959 — the 0.9% Additional Medicare Tax, reconciled
The 0.9% surtax hits earnings above $200k/$250k/$125k, but employers withhold on any single job over $200k regardless of filing status. Form 8959 settles the mismatch — refunding over-withholding, billing the two-job gap.