Economic nexus exposure, priced to the month

Price the uncollected sales tax, penalty and interest you have been carrying since the month you crossed a US state's economic nexus threshold.

The threshold test this state uses Sales into this state, rolling 12 months $ Separate orders into this state, same 12 months orders Date you passed the threshold Run the clock as of Average monthly sales into this state since then $ Combined state and local rate you should have charged % State failure-to-file and pay penalty % State interest on unpaid tax, annual % Lookback this state allows in a voluntary disclosure months

Threshold test	—
Months collecting nothing	—	months
Tax you should have collected	—	$
Penalty on that tax	—	$
Interest accrued to date	—	$
Carried today	—	$
Six more quiet months add	—	$
Still saveable by voluntary disclosure	—	$

Keep this run. Export every state you run to .csv for the file, and set dated browser reminders before a lookback window or a quarter closes.

$60 once · one licence key per person or team seat · A bookkeeper at $75/hour needs about four hours per state to test the threshold and rebuild the year - $300 per state.

Four threshold shapes, not one number
States do not share one test. The clock carries the four live shapes - sales only at $100,000, sales or 200 transactions, sales only at $500,000, and sales plus 100 transactions - so a seller picks the shape their state uses instead of trusting a single $100,000 answer. Source: the Streamlined Sales Tax Governing Board remote-seller pages at streamlinedsalestax.org and the state revenue department pages they link, checked 2026-09-21.

Month-by-month accrual, not a flat multiply
Tax accrues at the end of each exposed month and interest runs only on the months already gone by, so the oldest month carries the most interest and the newest carries none. That is why a hand calculation of rate times total sales overstates the newest months and understates the oldest.

The price of six more quiet months
The same run is repeated six months further out and the difference is shown on its own line, so the cost of postponing registration to the next quarter is a number rather than a feeling.

What a voluntary disclosure still saves
A voluntary disclosure agreement normally waives the penalty and limits the lookback to a fixed number of months. The clock prices the penalty plus any tax that falls outside that lookback - the part that stops being saveable the day the state sends its first contact letter.

Your figures never leave the tab
Sales, orders and rates are computed in the page. The only outbound call the extension ever makes is licence-key validation to api.polar.sh, which sends the key and nothing else.

Open full tool → getreadystack.com