Guides
Each guide works through real numbers from the same engine as our calculators, and links to the tool that does the sum for your own situation.
Paychecks and withholding
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401(k) and HSA limits for 2026
The 2026 401(k) limit is $24,500, HSA $4,400 self-only and $8,750 family. Catch-ups, per-paycheck amounts and what maxing out costs.
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Bonus tax and supplemental wages
Why bonuses look over-taxed: the 22% flat rate, the aggregate method, the 37% rate over $1,000,000, and what the bonus really costs at tax time.
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FICA and the Social Security wage base
Social Security stops at $184,500 of wages in 2026; Medicare never does. See the paycheck where it stops, two-job refunds and the extra Medicare tax.
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How to fill out a W-4
What each step of Form W-4 does to your paycheck, with 2026 examples for two-earner couples, parents claiming $2,200 a child and side income.
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How to read a pay stub
A real $72,000 California paycheck taken apart: gross pay, 401(k), section 125, federal and state tax, FICA, SDI, year-to-date columns and why they differ.
Tax rules and rates
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Local income taxes on wages
Which cities, counties and school districts tax wages in 2026, how resident and commuter rates differ, and what each takes from a $75,000 salary.
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Marginal vs effective tax rate
Your tax bracket is not your tax rate. A $85,000 salary is in the 22% bracket but pays 11.61% of income in federal tax. How both rates work.
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No tax on overtime, explained
The overtime deduction covers only the half-time premium, up to $12,500 ($25,000 joint). Worked examples, the phase-out, state daily overtime and the W-4.
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No tax on tips, explained
The federal tips deduction: up to $25,000 of qualified tips, the phase-out from $150,000, what still gets taxed, and worked examples for servers and bartenders.
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Quarterly estimated taxes
Estimated tax due dates for 2026, the 90% and 100% safe harbors that avoid a penalty, and how much a freelancer or side business should pay each time.
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State reciprocity agreements
Which states have reciprocal agreements on wages, the forms that switch them on, and what a cross-border commuter on $75,000 pays with and without one.
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States with no income tax, and what they charge instead
The 9 states that do not tax wages, take-home pay on $75,000 in each, and the payroll levies, sales taxes and property taxes that make up the difference.
Buying and refinancing a home
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How much house can I afford?
How lenders' 28% and 36% ratios turn a salary into a home price, what debts, rates and property tax do to it, and a cautious limit based on take-home pay.
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PMI explained
Private mortgage insurance on a $400,000 home: the monthly cost at different down payments, the 80% and 78% cancellation rules, and how to drop it years early.
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Refinance break-even
Why closing costs divided by monthly saving understates the break-even point, how resetting the term and rolling in costs change it, with a $280,000 example.