1. Your exempt sales
A CSV or pasted spreadsheet range with a header row, one row per invoice. Columns recognised: invoice, date, customer, state (ship-to), amount, tax charged, exemption reason (blank for a taxable sale). Taxable sales are ignored.
2. Certificates on file
Columns recognised: customer, state, certificate number, type (resale, manufacturing, government, nonprofit, agriculture), date signed, expires. Leave type blank for resale.
3. Rates and rules
Choose files or paste the lists, then click Check my certificates.
Result
Customers to chase, biggest tax first
| Customer | States | Unsupported sales | Tax at stake | Why |
|---|
By state
| State | Rate | Exempt sales | Unsupported | Tax at stake |
|---|
Every exempt sale
| Invoice | Date | Customer | State | Amount | Result | Tax at stake |
|---|
Request letter
Certificates close to lapsing
Findings
The rules it applies, and what it leaves out
- An exempt sale is tested against a certificate for the same customer, the same state and the same reason. Customer names are matched ignoring Inc, LLC and punctuation; a near-miss is flagged for you to confirm, never silently merged.
- Results: covered; no certificate; certificate for a different state; certificate expired on the sale date; certificate signed after the sale; certificate for a different reason (a resale certificate does not support a manufacturing claim); certificate with no number (kept as on file, flagged).
- Out-of-state delivery is shown as not needing a buyer certificate, because shipping records support it.
- Tax at stake is the sale amount times the rate you give for the ship-to state. It excludes interest and penalties, and it is only as good as your rates.
- Not decided: whether a state accepts a certificate obtained after the sale, how long a certificate stays valid in each state, whether a buyer qualifies for the exemption claimed, whether a certificate is the right form, the look-back period of an audit, or whether you owe tax on a sale at all. Those are your state's rules and your adviser's call; this page applies the dates and rates you give it.
Common questions
What happens in a sales tax audit if I don't have an exemption certificate?
In most states the seller, not the buyer, owes the tax on an exempt sale it cannot support with a valid certificate. Auditors usually sample invoices, find the exempt ones, and ask for the certificate behind each; sales with none are assessed at the state and local rate, plus interest and often a penalty. This page finds those sales before an auditor does. It is not tax advice; your state's department of revenue sets the rules.
Can I get a certificate after the sale?
Some states let a seller accept a certificate obtained within a set period after the sale or during an audit; others require it at the time of sale. The rule is the state's, and this page does not guess it: a certificate dated after the sale is flagged as late with the number of days, so you can check that state's rule.
Do exemption certificates expire?
It depends on the state and the type of certificate. Some never lapse while the buyer keeps buying, some expire after a fixed period, and some must be renewed on a schedule. Enter an expiry for each certificate if it has one, or set a number of years to apply to every certificate that has none.
What counts as a sale needing a certificate?
A sale you invoiced without tax on the buyer's claim of exemption, such as resale, manufacturing, government, nonprofit or agricultural use. A sale delivered outside the state is proved by shipping records rather than a buyer certificate, so it is listed as not needing one.
How is the exposure figure worked out?
Each unsupported sale's amount times the combined state and local rate you enter for the state it shipped to, in whole cents. It is the tax at stake before interest and penalties, and it is only as good as the rates you enter.
Is my sales data uploaded anywhere?
No. Both lists are read in your browser and nothing is sent; a test in the code asserts there are no network calls.