CPA audit readiness

2026 Payroll Engine Methodology Review

This page exposes the latest generated test report, the authoritative source set behind the 2026 payroll data, and the jurisdictions that need extra scrutiny during review.

2026 data updated · Last checked June 20, 2026

Source: Latest audit report JSON (download below)

Planned Review Scope and Report Summary

Overall status

PASS

Combined test and smoke-test outcome

Engine tests

PASS

492 passed · 0 failed

Smoke tests

PASS

204 passed · 0 failed

Flagged states

Jurisdictions that need extra CPA review

Generated at

July 27, 2026 at 05:54 PM UTC

scripts/generate-cpa-audit-report.mjs

Download the full report: cpa-audit-report-2026-07-27.json or cpa-audit-report-latest.json

Authoritative Sources

Federal withholding: IRS Publication 15-T (effective 2026-01-01)
Social Security wage base: SSA 2026 Social Security Wage Base (184,500 wage base)
Medicare withholding: IRS Topic 751
Additional Medicare tax: IRS Topic 560
State income tax: All 51 state and DC Departments of Revenue — 2026 withholding tables

Flagged Jurisdictions

These states changed recently and deserve extra manual review during the CPA pass.

West Virginia

2026 data · Updated June 20, 2026· West Virginia DOR492 regression tests passing

Top rate 4.58% with retroactive change effective 2026-06-12.

Retroactive rate reduction effective June 12, 2026. Effective 2026-03-01.

Priority action: Verify against official 2026 withholding tables and confirm or correct if needed

South Carolina

2026 data · Updated June 20, 2026· South Carolina DOR492 regression tests passing

WH-1603F uses allowance-dependent deductions and source-backed withholding bands.

SC W-4 allowance-dependent withholding formula. Effective 2026-01-01.

Priority action: Recheck WH-1603F during the next quarterly verification cycle

Mississippi

2026 data · Updated June 20, 2026· Mississippi DOR492 regression tests passing

Flat 4.00% rate with the first $10,000 of taxable income exempt.

Phase-down rate with first $10,000 exempt. Effective 2026-01-01.

Priority action: Verify against official 2026 withholding tables and confirm or correct if needed

Utah

2026 data · Updated June 20, 2026· Utah DOR492 regression tests passing

Flat 4.45% rate in force for 2026.

Reduced flat rate remains in effect. Effective 2026-01-01.

Priority action: Verify against official 2026 withholding tables and confirm or correct if needed

Montana

2026 data · Updated June 20, 2026· Montana DOR492 regression tests passing

Graduated schedule includes 4.70% lower rate and 5.65% top rate.

Reduced top rate and updated bracket widths. Effective 2026-01-01.

Priority action: Verify against official 2026 withholding tables and confirm or correct if needed

Known Limitations

ExactTakeHome models W-2 employee withholding, not final tax liability.
Local taxes are only modeled where a route explicitly supports them.
Self-employment tax, AMT, and investment income are outside this calculator scope.
State-specific manual review is still required for any jurisdiction with recent legislative changes.

Test Execution Report

The full engine regression suite is represented by 404+ regression tests. The generated audit report stores the latest raw output below for CPA review.

Engine test output


> @takehome/engine@0.1.0 test /vercel/path0/packages/engine
> vitest run --coverage


[1m[7m[36m RUN [39m[27m[22m [36mv2.1.9 [39m[90m/vercel/path0/packages/engine[39m
      [2mCoverage enabled with [22m[33mv8[39m

 [32m✓[39m src/__tests__/qualified-tips-deduction.test.ts [2m([22m[2m5 tests[22m[2m)[22m[90m 4[2mms[22m[39m
 [32m✓[39m src/__tests__/overtime-deduction.test.ts [2m([22m[2m7 tests[22m[2m)[22m[90m 5[2mms[22m[39m
 [32m✓[39m src/__tests__/multi-state.test.ts [2m([22m[2m9 tests[22m[2m)[22m[90m 10[2mms[22m[39m
 [32m✓[39m src/__tests__/rsu.test.ts [2m([22m[2m7 tests[22m[2m)[22m[90m 10[2mms[22m[39m
 [32m✓[39m src/paycheckcity-reference.test.ts [2m([22m[2m10 tests[22m[2m)[22m[90m 9[2mms[22m[39m
 [32m✓[39m src/__tests__/supplemental-income.test.ts [2m([22m[2m5 tests[22m[2m)[22m[90m 11[2mms[22m[39m
 [32m✓[39m src/__tests__/retirement-income.test.ts [2m([22m[2m12 tests[22m[2m)[22m[90m 14[2mms[22m[39m
 [32m✓[39m src/__tests__/foreign-earned-income.test.ts [2m([22m[2m15 tests[22m[2m)[22m[90m 16[2mms[22m[39m
 [32m✓[39m src/__tests__/self-employment.test.ts [2m([22m[2m10 tests[22m[2m)[22m[90m 18[2mms[22m[39m
 [32m✓[39m src/pretax-deductions.test.ts [2m([22m[2m26 tests[22m[2m)[22m[90m 26[2mms[22m[39m
 [32m✓[39m src/__tests__/gross-up.test.ts [2m([22m[2m8 tests[22m[2m)[22m[90m 17[2mms[22m[39m
 [32m✓[39m src/__tests__/stock-options.test.ts [2m([22m[2m10 tests[22m[2m)[22m[90m 37[2mms[22m[39m
 [32m✓[39m src/__tests__/paystub-match.test.ts [2m([22m[2m40 tests[22m[2m)[22m[90m 49[2mms[22m[39m
 [32m✓[39m src/calc.test.ts [2m([22m[2m328 tests[22m[2m)[22m[90m 95[2mms[22m[39m

[2m Test Files [22m [1m[32m14 passed[39m[22m[90m (14)[39m
[2m      Tests [22m [1m[32m492 passed[39m[22m[90m (492)[39m
[2m   Start at [22m 17:54:19
[2m   Duration [22m 959ms[2m (transform 1.19s, setup 0ms, collect 4.22s, tests 321ms, environment 3ms, prepare 1.50s)[22m

[34m % [39m[2mCoverage report from [22m[33mv8[39m
-------------------|---------|----------|---------|---------|-------------------
File               | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
-------------------|---------|----------|---------|---------|-------------------
All files          |     100 |      100 |     100 |     100 |                   
 src               |     100 |      100 |     100 |     100 |                   
  calc.ts          |     100 |      100 |     100 |     100 |                   
  ...k-fixtures.ts |     100 |      100 |     100 |     100 |                   
  ...ned-income.ts |     100 |      100 |     100 |     100 |                   
  gross-up.ts      |     100 |      100 |     100 |     100 |                   
  index.ts         |     100 |      100 |     100 |     100 |                   
  multi-state.ts   |     100 |      100 |     100 |     100 |                   
  ...-deduction.ts |     100 |      100 |     100 |     100 |                   
  paystub-match.ts |     100 |      100 |     100 |     100 |                   
  ...deductions.ts |     100 |      100 |     100 |     100 |                   
  ...-deduction.ts |     100 |      100 |     100 |     100 |                   
  ...ent-income.ts |     100 |      100 |     100 |     100 |                   
  rsu.ts           |     100 |      100 |     100 |     100 |                   
  ...employment.ts |     100 |      100 |     100 |     100 |                   
  stock-options.ts |     100 |      100 |     100 |     100 |                   
  ...tal-income.ts |     100 |      100 |     100 |     100 |                   
  types.ts         |     100 |      100 |     100 |     100 |                   
  ...date-input.ts |     100 |      100 |     100 |     100 |                   
 ...ate-strategies |     100 |      100 |     100 |     100 |                   
  ...percentage.ts |     100 |      100 |     100 |     100 |                   
  ...-allowance.ts |     100 |      100 |     100 |     100 |                   
  ...tion-level.ts |     100 |      100 |     100 |     100 |                   
  ...-deduction.ts |     100 |      100 |     100 |     100 |                   
  flat.ts          |     100 |      100 |     100 |     100 |                   
  index.ts         |     100 |      100 |     100 |     100 |                   
  ...age-method.ts |     100 |      100 |     100 |     100 |                   
  none.ts          |     100 |      100 |     100 |     100 |                   
  ...ge-formula.ts |     100 |      100 |     100 |     100 |                   
  ...riod-table.ts |     100 |      100 |     100 |     100 |                   
  ...ion-credit.ts |     100 |      100 |     100 |     100 |                   
  progressive.ts   |     100 |      100 |     100 |     100 |                   
  shared.ts        |     100 |      100 |     100 |     100 |                   
  ...g-schedule.ts |     100 |      100 |     100 |     100 |                   
  ...age-method.ts |     100 |      100 |     100 |     100 |                   
-------------------|---------|----------|---------|---------|-------------------

Smoke test output

  OK https://exacttakehome.com/
  OK https://exacttakehome.com/calculator/
  OK https://exacttakehome.com/calculator/california/
  OK https://exacttakehome.com/calculator/texas/
  OK https://exacttakehome.com/calculator/new-york/
  OK https://exacttakehome.com/calculator/maine/
  OK https://exacttakehome.com/calculator/south-carolina/
  OK https://exacttakehome.com/salary/75k/
  OK https://exacttakehome.com/salary/100k/
  OK https://exacttakehome.com/salary/200k/
  OK https://exacttakehome.com/salary/500k/
  OK https://exacttakehome.com/salary/250k/
  OK https://exacttakehome.com/salary/45k/
  OK https://exacttakehome.com/salary/85k/
  OK https://exacttakehome.com/salary/120k/
  OK https://exacttakehome.com/salary/175k/
  OK https://exacttakehome.com/salary/108k/
  OK https://exacttakehome.com/salary/250k/?state=tx
  OK https://exacttakehome.com/compare/california-vs-texas/
  OK https://exacttakehome.com/blog/
  OK https://exacttakehome.com/ads.txt
  OK https://exacttakehome.com/about/
  OK https://exacttakehome.com/research/best-states-take-home-pay/
  OK https://exacttakehome.com/contact/
  OK https://exacttakehome.com/methodology/
  OK https://exacttakehome.com/methodology/federal/
  OK https://exacttakehome.com/methodology/embed/
  OK https://exacttakehome.com/privacy-policy/
  OK https://exacttakehome.com/salary/
  OK https://exacttakehome.com/salary/by-profession/
  OK https://exacttakehome.com/salary/profession/software-engineer/california/
  OK https://exacttakehome.com/compare/
  OK https://exacttakehome.com/compare/turbotax-vs-free-filing/
  OK https://exacttakehome.com/compare/turbotax-vs-freetaxusa/
  OK https://exacttakehome.com/compare/turbotax-vs-taxact/
  OK https://exacttakehome.com/compare/gusto-vs-quickbooks-payroll/
  OK https://exacttakehome.com/compare/gusto-vs-adp-run/
  OK https://exacttakehome.com/research/how-is-overtime-taxed-2026/
  OK https://exacttakehome.com/research/w2-box-12-codes-explained-2026/
  OK https://exacttakehome.com/research/why-is-my-w2-different-from-my-salary-2026/
  OK https://exacttakehome.com/research/how-to-check-w2-withholding-accuracy-2026/
  OK https://exacttakehome.com/research/is-turbotax-worth-it-2026/
  OK https://exacttakehome.com/research/gusto-pricing-breakdown-2026/
  OK https://exacttakehome.com/research/why-is-my-bonus-taxed-so-high-2026/
  OK https://exacttakehome.com/raise-impact-calculator/
  OK https://exacttakehome.com/tools/life-event-paycheck/
  OK https://exacttakehome.com/tools/life-event-paycheck/marriage/
  OK https://exacttakehome.com/tools/life-event-paycheck/child/
  OK https://exacttakehome.com/compare/gusto-vs-manual-payroll/
  OK https://exacttakehome.com/compare/california-vs-texas/
  OK https://exacttakehome.com/compare/new-york-vs-texas/
  OK https://exacttakehome.com/compare/california-vs-washington/
  OK https://exacttakehome.com/compare/florida-vs-new-york/
  OK https://exacttakehome.com/compare/florida-vs-new-jersey/
  OK https://exacttakehome.com/compare/mass

Review Notes

The audit report is generated by scripts/generate-cpa-audit-report.mjs and should be refreshed after each major data change or before sending materials to the CPA.

Questions about the methodology belong on the methodology page or in the public changelog.