Paycheck Breakdown: Where $10k Gross Goes

Run a $120,000 annual salary through the 2026 payroll framework and $4,080 of every $10,000 gross paycheck disappears before it touches a bank account — for a single filer in Texas with full pre-tax elections. California residency pushes that figure to $4,445. These are not estimates. They are the product of IRS Revenue Procedure 2025-32, IRS Notice 2025-67, and the Social Security Administration’s 2026 wage base, applied in sequence to a W-2 paycheck.

The analysis below models three filing scenarios at $120,000 gross annual pay ($10,000 per month) using verified 2026 federal parameters and 2025 California Franchise Tax Board rates — the most current FTB schedule available for withholding purposes. Each scenario traces the full gross-to-net pay waterfall, calculates the Finluxy Net Pay Rate with and without pre-tax benefit elections, and isolates the dollar contribution of every deduction layer.

Key Figures at a Glance

Sources: IRS Revenue Procedure 2025-32 (2026 brackets, standard deduction); IRS Notice 2025-67 (401k limit $24,500); IRS Revenue Procedure 2025-19 (HSA limits $4,400 single / $8,750 family); Social Security Administration (2026 wage base $184,500, rate 6.2%); California Franchise Tax Board 2025 tax rate schedules (most current available). Calculations by Finluxy.

The 2026 Payroll Framework

Three deduction layers hit a paycheck before any dollar reaches a bank account: pre-tax benefit elections, FICA withholding, and income tax. They are not independent. Pre-tax elections reduce federal taxable income — but 401(k) deferrals do not reduce the FICA withholding base. Only HSA contributions made through a Section 125 cafeteria plan escape Social Security and Medicare withholding entirely. That asymmetry is the mechanism behind one of the most consistently misunderstood figures in take-home pay math.

For 2026, the 401(k) elective deferral limit rose to $24,500 from $23,500 in 2025, per IRS Notice 2025-67. The HSA contribution limits moved to $4,400 for single coverage and $8,750 for family coverage, per IRS Revenue Procedure 2025-19. The Social Security Administration set the 2026 FICA withholding base at $184,500 — up $8,400 from $176,100 in 2025 — at the same 6.2% rate. Medicare remains at 1.45% with no wage ceiling, plus a 0.9% Additional Medicare Tax surcharge on earnings above $200,000 for single filers. At $120,000 gross, none of those wage ceilings are yet in play. The full picture of how these thresholds shift at higher incomes is covered in the gross-to-net guide from $150k to $500k.

Federal brackets for 2026, from IRS Revenue Procedure 2025-32, place the 22% rate at taxable income above $50,400 for single filers and $100,800 for married filers. The 24% rate begins at $105,700 (single) and $211,400 (MFJ). A $120k earner who maxes pre-tax elections lands at $75,000 in federal taxable income — well inside the 22% bracket, never touching 24%. Without those elections, the same earner sits at $103,900 in taxable income — still inside the 22% bracket by $1,800, but uncomfortably close to the boundary. The cost of crossing from 22% to 24% is exactly the kind of math that full elections are designed to prevent.

Full Waterfall: Single Filer, Texas, $120k Gross

Note: FICA base is $115,600 because HSA contributions made through a Section 125 cafeteria plan are FICA-exempt; 401(k) deferrals are not. Federal tax on $75,000: 10% on $12,400 ($1,240) + 12% on $38,000 ($4,560) + 22% on $24,600 ($5,412) = $11,212. Sources: IRS Revenue Procedure 2025-32, IRS Notice 2025-67, IRS Revenue Procedure 2025-19, SSA 2026; Finluxy analysis.

The federal income tax of $11,212 on $75,000 of taxable income works out to a 9.3% effective drag on gross pay — built from three bracket layers: 10% on the first $12,400 ($1,240), 12% on the next $38,000 ($4,560), and 22% on the remaining $24,600 ($5,412). No dollar of this earner’s income touches 24%. The 24% bracket for single filers in 2026 does not begin until taxable income exceeds $105,700.

Without pre-tax elections, the identical earner keeps $7,771 in monthly cash — $1,851 more per paycheck. But that comparison omits what elections actually accomplish. The $28,900 redirected to 401(k) and HSA is still the earner’s money. What elections eliminate is $6,695 in government withholding annually: $6,358 in avoided federal income tax plus $337 in avoided FICA withholding on the HSA contribution. That $6,695 is the real return on elections — a guaranteed first-year gain that increases net worth without the earner receiving a cent less in gross pay. For a detailed look at the monthly arithmetic, how pre-tax elections increase monthly net pay shows the full interaction across income levels.

One figure that gets glossed over: the Finluxy Net Pay Rate without elections is 77.7% — higher than the 59.2% with elections. The metric doesn’t lie. Without elections, more cash lands in the bank each month, but $6,695 of additional wealth is surrendered to taxes. The higher Net Pay Rate without elections reflects a less efficient allocation of gross pay, not a better financial outcome.

California Adds $365 Per Paycheck

Same earner. Same federal rules. Same elections. Adding California residency costs $4,380 in annual state income tax — $365 per $10,000 paycheck — and drops the Finluxy Net Pay Rate from 59.2% to 55.6%. That single geographic variable represents a 3.6-percentage-point reduction in net pay rate on otherwise identical gross pay.

California’s 2025 FTB tax rate schedule — the most current schedule available for 2026 withholding approximation — applies nine progressive brackets from 1% to 12.3%, with a $5,706 standard deduction for single filers. After subtracting the pre-tax deductions and the state standard deduction, California taxable income for this earner reaches $85,394. The marginal rate at that level is 9.3%. The top brackets — 10.3%, 11.3%, and 12.3% — do not engage until California taxable income clears $371,479. The effective California state rate on gross pay for this scenario is approximately 3.7%.

The gap between the California and federal standard deductions is a structural cost that surprises many transplants. California’s $5,706 single standard deduction versus the federal $16,100 means California taxable income is $10,394 higher than federal taxable income, all else equal. Every dollar of that gap runs through the 9.3% bracket for this earner — adding roughly $968 in state tax relative to what a California deduction matching the federal level would produce. For a full state-by-state comparison at the next income tier, the $150k salary take-home breakdown by state shows how this gap compounds upward. The California versus Texas take-home at $200k is even more pronounced once income climbs into higher marginal territory.

California figures use 2025 FTB tax rate schedules (FTB Form 540 tax rate schedules, 2025), standard deduction $5,706 single. Federal figures use IRS Revenue Procedure 2025-32 (2026). Finluxy analysis.

Filing Status: The Biggest Federal Lever at This Income Level

At $120,000 household gross, married filing jointly produces federal taxable income of $54,550 — after the $33,250 in combined pre-tax elections (401k $24,500 plus family HSA $8,750) and the $32,200 MFJ standard deduction. That is $20,450 less taxable income than the equivalent single filer. Federal income tax falls to $6,050, against $11,212 for the single scenario — a $5,162 annual difference on identical gross pay.

The MFJ Finluxy Net Pay Rate reaches 60.2% in Texas, against 59.2% for the single filer — a 1.0 percentage-point gap that looks narrow but represents $1,144 in additional annual take-home from filing status alone. The MFJ earner also contributes $4,350 more annually to pre-tax accounts (the family HSA adds $4,350 over the single HSA) while paying less tax, which is the combination that maximizes long-run wealth accumulation. For the full picture of how this advantage scales, the married versus single take-home at $300k household income shows where the MFJ benefit starts compressing under the alternative minimum tax framework.

FICA withholding is slightly lower for the MFJ earner in this model — $709 per month versus $737 for the single filer. That’s not a filing-status benefit directly; it is a consequence of the larger family HSA deduction creating a wider FICA-exempt base. The Section 125 HSA exemption reduces the FICA-taxable base by $4,350 more than the single HSA, saving the MFJ earner an additional $333 annually in combined Social Security and Medicare withholding. Small, but real.

The Overlooked Figure: FICA Is Eating More Than Most Earners Realize

Coverage of take-home pay almost universally centers on income tax. The FICA withholding number gets a line item and moves on. At $120,000 gross in 2026, FICA costs this single earner $8,843 annually — 74% of what federal income tax costs — and it begins on the first dollar, ignores the standard deduction entirely, and is indifferent to filing status. Pre-tax 401(k) contributions do not reduce it. No amount of bracket management touches it.

There is one FICA lever available to a W-2 employee: the Section 125 HSA deduction. Maxing the single HSA at $4,400 saves $337 in FICA annually ($4,400 × 7.65%). The family HSA at $8,750 saves $669. Those are the only FICA savings a W-2 earner controls. The monthly net pay impact of 401(k) and HSA elections breaks down exactly how each dollar of those deductions flows through both the income tax and FICA layers.

What the data shows that most coverage overlooks: the FICA burden is proportionally heavier at lower income levels than at $120k, because the progressive structure of income tax gives lower earners deduction and bracket relief that FICA never provides. At $80k gross, FICA consumes a larger share of income relative to income tax than it does here. At the same time, earners above the Social Security wage base — $184,500 in 2026 — watch their effective FICA rate drop mid-year as Social Security withholding ceases. For reference, the $80k take-home breakdown by state illustrates the FICA-to-income-tax ratio at a lower income tier. A $120k earner won’t hit the Social Security ceiling, but high earners above $184,500 can see a meaningful mid-year paycheck increase when it cuts off.

Finluxy Net Pay Rate — Full Summary

Finluxy Net Pay Rate = Annual net take-home ÷ Gross annual salary × 100. “With elections” = full 401(k) at $24,500 + HSA at $4,400 (single) or $8,750 (MFJ family). “Tax & FICA savings” = reduction in federal income tax plus FICA versus no pre-tax elections. MFJ savings is an estimate; California state tax savings from elections not separately broken out. Sources: IRS, SSA, FTB; Finluxy analysis, 2026.

The spread across all three with-elections scenarios is 4.6 percentage points — from the MFJ Texas high of 60.2% to the single California low of 55.6%. On a $120,000 salary, that 4.6-point range equals $5,524 annually. State of residence and filing status are doing more marginal work at this income level than any additional tax optimization move short of maxing a backdoor Roth or a mega-backdoor 401(k). The $200k income net pay breakdown is where state tax drag and bracket positioning begin to diverge meaningfully from this picture.

Context for $150k+ Households

At $120k gross, the marginal federal rate is 22% — with no pre-tax elections, the earner sits at $103,900 in federal taxable income, just $1,800 below the 24% threshold. A $2,000 bonus or a year-end pay increase tips this earner into 24% territory on the incremental dollars. That 2-percentage-point jump costs 2 cents on every dollar above $105,700, which is modest in isolation but adds up quickly for earners receiving stock compensation, variable bonuses, or raises. The bonus take-home analysis at the 37% bracket shows how supplemental wages interact with withholding at the extreme, and the pattern for earners at lower brackets is structurally similar.

Households pushing past $150k face a sharper version of the same waterfall. A single earner at $150k gross with full 2026 elections would carry federal taxable income of approximately $109,400 — past the 24% threshold — with every marginal dollar above $105,700 taxed at 24 cents federally before state and FICA. The $150k salary take-home by state and the marginal dollar yield at $250k extend this analysis into territory where the 32% bracket enters the picture and the Additional Medicare Tax begins compressing net pay further.

One reframe that the Finluxy Net Pay Rate makes visible: at 59.2%, the single Texas earner with full elections deposits $5,920 per $10,000 paycheck into the bank. But the total dollars working for that earner — cash received plus 401(k) balance accrual plus HSA balance — equals $8,328 per $10,000 gross. The 59.2% figure measures what clears the bank. The correct number for long-run wealth analysis is 69.4%, reflecting all dollars the earner controls, including tax-deferred accounts. The 10.2-percentage-point gap between those two figures is what pre-tax elections actually do: they redirect income from the bank account into wealth-building accounts, eliminating the government’s cut in the process. For earners who have not yet maxed their elections, that 10.2 points is the most accessible remaining yield in their paycheck. The 401(k) pre-tax impact at $100k gross and the real after-tax gap between $100k and $150k provide additional reference points on the same underlying math.