Trust · January 1, 2026

Methodology and sources

Rates live in src/data/states.ts. There is no live tax service. When a legislature or a city changes a rate, this file has to be edited and the site rebuilt.

Primary sources

Tax Foundation, State and Local Sales Tax Rates, 2026 (as of January 1, 2026) (as of 2026-01-01)
Tax Foundation, State and Local Sales Tax Rates, 2025 (as of January 1, 2025) (as of 2025-01-01)

Tax Foundation compiles Sales Tax Clearinghouse ZIP data and state revenue publications into population-weighted local averages. We transcribed the January 1, 2026 table for the working calculator and kept January 1, 2025 combined figures for comparison. We did not license Sales Tax Clearinghouse itself.

What we store per state

Statewide base rate (percent)
Average local rate, 2026 and 2025
Average combined rate, 2026 and 2025
Maximum reported local add-on (2026)
A high-level sourcing label and a short note

Calculator math

Add tax: tax = round(amount × rate / 100),total = amount + tax. Reverse:preTax = round(total / (1 + rate / 100)),tax = total − preTax. Rounding is half-up to cents.

What we leave out

ZIP+4 districts, product taxability, exemptions, holidays, marketplace facilitator splits, and bracket schedules. Those omissions are why the banner says the figures are approximate and not Avalara-grade.

Sourcing labels are a teaching map compiled from public explainers (department bulletins, Streamlined Sales Tax materials, and practitioner summaries). They are not a legal matrix.