In an audit, your client has to prove every exempt sale.

An exempt sale without proof is a taxable sale.

In Washington the seller has to prove a sale is exempt. Without the buyer's reseller permit or other exemption proof on file, the Department of Revenue treats it as a taxable retail sale and your client owes the sales tax on it, for up to four years back. Missing proof is one of the most common audit adjustments.

An exempt sale without proof is a taxable sale.

The proof

Sundry keeps the proof, for every client.

  1. Sync

    Customers come from your client's books.

  2. Request

    Pick the customer and the proof. Sundry emails the customer a link that works for seven days. Send again issues a new link and cancels the old one.

  3. Sign

    The customer fills in the state's own form and signs it.

  4. Verify

    Sundry reads it against the form's requirements. When a buyer sends proof through Sundry's request link and Sundry can't read it, the buyer is asked for a clearer copy.

    A proof marked Verified by Sundry is covered by the Sundry Guarantee.

MaintainKessler Bakery LLC · September 2026
Customers and exemption proofsRequests first, then by name · 214 customers
Proof forProof typeStatus
Cascade GrocersResale certificateRequested 3d ago
Harbor HotelsResale certificateRequested 1d ago
Green Lake ElementaryGovernment exemptionValid · 2028
Muckleshoot CaféTribal exemptionExpired Sep 2
WA Dept. of CorrectionsState government exemptionValid · 2027
Product determinations
1,412 products · all determined
Categorization covered by the Sundry Guarantee.
Requests first, then by name.

Chasing paper is the hour nobody bills for.

For a small accounting or bookkeeping firm, exemption proof is scattered across every client. Sundry sends the request and reads what comes back. Each company's proofs are in one place, with what's waiting on a buyer listed first. Your staff step in only where a person is needed.

More clients. Not more hours.

The return

The return only exempts what is proven.

A sale is exempt on the return only when a verified proof is in date at the sale. For a resale, Sundry allows the 120 days Washington gives to obtain it, as long as the proof's effective date is on or before the sale.

The Sundry Worksheet shows the exempt sales and how many are covered by a proof before your client signs off. Nothing goes forward until you approve it.

Washington

What Washington accepts as proof of an exempt sale

What is the difference between a reseller permit and other exemption proof?
A reseller permit is the buyer's registration to buy goods for resale without paying sales tax. Other exemption proof is a form the buyer signs to claim a specific exemption, such as a farmer's purchase of seed, feed or fertilizer, or a certificate the Department of Revenue issues. Sundry supports both.
When does a Washington seller need the reseller permit or other proof?
At the time of the sale, or within 120 days of it. In an audit, the seller generally has 120 days from the initial audit results to produce a missing one (WAC 458-20-102). The proof's effective date must still be on or before the sale.
How long should a seller keep exemption proof?
The Department of Revenue says to keep business records for five years. An assessment can reach back four years (RCW 82.32.050(4)).
Which exemption proofs does Sundry support?
The Washington reseller permit and ten of the Department of Revenue's exemption forms: REV 27 0002, 0003, 0021, 0032, 0036, 0049, 0050, 0055, 0063 and REV 36 0001. The library below lists the proofs Sundry supports.
What happens to a sale without proof?
The auditor reclassifies it as a retail sale, and your client owes the sales tax on it (RCW 82.04.470). On a Sundry return, a sale without a verified proof in date is not exempted.
Does Sundry check a reseller permit or other proof?
Yes. Sundry reads every proof that comes back: the form, the required fields, the dates in effect and the buyer's ID. When a buyer sends proof through Sundry's request link and Sundry can't read it, the buyer is asked for a clearer copy.

The guarantee

The Sundry Guarantee covers our determination and every proof we verify. If either is wrong and your client underpays as a result, we refund what you paid us for that return. See the Sundry Guarantee.

Exemption proofs Sundry supports

Sundry supports the Washington exemption proofs listed here: the state forms buyers sign, certificates the Department of Revenue issues, permits and other documents. Find yours by name, form number or statute.

Use (45)

Entity (12)

Department-issued (6)

Resale permit (3)