How to Fill Out a New York Resale Certificate (ST-120): Field by Field

To fill out a New York resale certificate on Form ST-120, enter the seller’s legal name and address, mark whether the form is a single-purchase or blanket certificate, add your business name, address, and New York Certificate of Authority number, describe your business and the goods or services you’re buying for resale, then sign, date, and deliver the form to your seller. The certificate stays with the seller as proof the sale was exempt; you never file it with the state.¹

The form is short. The trouble is in the details: a missing field, the wrong certificate type for your business, or a description that doesn’t match what you actually sell can void the exemption and expose you to tax, penalties, and interest years later.

Before You Start: Are You Eligible

To issue an ST-120, you need a New York Certificate of Authority, which is the state’s sales tax vendor registration. Registration is free and you apply through the Department of Taxation and Finance.² That certificate is what lets you both collect sales tax on your own sales and issue exemption certificates to your suppliers.³

The purchase you’re making has to be one of these:

Goods you’ll resell as-is to your customers.
Materials, parts, or packaging that will become a physical component of a product you sell.
A taxable service you’re going to resell to your own customers. New York taxes several categories of services, including information services, fabrication and processing, and repair or maintenance of tangible personal property.⁴

Contractors Use a Different Form

Construction contractors cannot use Form ST-120. Contractors who install materials into real property are treated as the end users of those materials, not resellers. If you’re a contractor buying supplies for a job, the form you need is ST-120.1, the Contractor Exempt Purchase Certificate, which has its own rules.¹

Buying From a New York Vendor When You’re Out of State

You can still use Form ST-120 if you’re an out-of-state business buying from a New York supplier. You don’t need a New York Certificate of Authority. Instead, you certify on the form that you aren’t required to register in New York, and you provide your sales tax registration number from your home state.¹ If your supplier is drop-shipping goods into another state on your behalf, that destination state’s rules control which certificate the supplier needs from you, not New York’s.

What to Have in Front of You

Gather everything before you open the form. Chasing down a registration number mid-way through is how blanks get left behind, and blanks are exactly what auditors look for.

The seller’s full legal name and business address.
Your legal business name and address, matching what’s on your Certificate of Authority.
Your Certificate of Authority number, or if you’re out of state, your home state sales tax registration number.
A clear description of what your business does and what it sells.
A specific description of the goods or services you’re buying under this certificate.

Download the current version of Form ST-120 (revised January 2026) directly from the Department of Taxation and Finance.⁵ Using an outdated version can get a sale rejected during an audit.

Filling Out the Form Field by Field

Seller Information

At the top of the form, enter the seller’s legal business name and full address. This ties the certificate to a specific vendor. One certificate covers one seller; you can’t hand the same completed form to multiple suppliers.

Single Purchase or Blanket Certificate

Mark whether the certificate covers a single transaction or serves as a blanket certificate for ongoing purchases of the same type from this seller.¹ More on choosing between the two below.

Purchaser Information

Enter your legal business name, address, and Certificate of Authority number. Then describe the nature of your business and the products or services you sell. Be specific. “Retail women’s clothing” is better than “retail.” “Wholesale electronics distributor” is better than “wholesale.” Vague descriptions raise questions during audits because they make it harder to see whether your purchases actually match your business.

Property or Services Being Purchased

Describe what you’re actually buying. On a single-purchase certificate, this should match the specific transaction. On a blanket certificate, describe the general category of goods or services you regularly purchase from this seller.

Signature and Date

The owner, a partner, or an authorized representative must sign, print their name and title, and date the form. New York accepts electronic signatures on exemption certificates, so you can complete and deliver the form digitally if both parties agree.¹

What You’re Certifying by Signing

Your signature is a statement under penalty of law that the purchases are genuinely for resale. The form warns that willfully issuing a false certificate to evade tax can be a felony.⁵ Read the certification block before you sign it. You’re taking on real exposure.

Single-Purchase or Blanket: Which to Mark

A single-purchase certificate covers one transaction. Fill it out, hand it over, done. If you buy from that same vendor next month, you’ll issue another one.

A blanket certificate covers all future purchases of the same general type from the same seller. It has no fixed expiration date and stays valid as long as you keep making exempt purchases from that vendor. You do need to issue an updated certificate if your address, registration number, or other information changes, and the seller can ask for a fresh copy at any time.¹

If you’re buying regularly from the same supplier, use a blanket certificate. Managing a separate form for every reorder eats time and multiplies the chances of a missing certificate turning up in an audit.

Giving the Form to Your Seller

Hand the completed ST-120 to your seller at the time of purchase, or as soon after as you can. The hard limit is 90 days after the sale. If the seller doesn’t have a properly completed certificate within that window, they lose their liability protection for not collecting tax on the transaction, and they’ll likely come back to you for the money.⁶

Keep a copy for your own records. If you’re audited, you’ll need to show that you either collected sales tax when you resold the item or reported use tax if you kept it.

If You End Up Using What You Bought

The most expensive mistake with an ST-120 is buying something tax-free for resale and then using it yourself. The moment you consume something you purchased under a resale certificate, you owe New York use tax on it.

You’re required to report this on your sales tax return and pay the tax you would have owed at the point of purchase. The form is explicit: “If you purchase tangible personal property or services for resale, but use or consume the tangible personal property or services yourself in New York State, you must report and pay the unpaid tax directly to New York State.”⁵

Honest changes of plan happen. You order extra inventory, some of it ends up in your own office. Report and pay the use tax promptly on your next return and you’re fine. What auditors don’t accept is a pattern of tax-free purchases with no resale revenue to match.

Penalties for Getting It Wrong on Purpose

Using a resale certificate to avoid tax on purchases you never intended to resell carries penalties designed to make the risk badly disproportionate to whatever tax you saved:

A penalty equal to 100% of the tax that should have been paid.
$50 for each fraudulent certificate issued.
Felony prosecution for willfully issuing a false certificate to evade tax, punishable by a substantial fine and possible jail time.
Revocation of your Certificate of Authority, which shuts down your ability to legally operate a taxable business in the state.⁵

You still owe the original unpaid tax plus interest on top. New York charges interest on unpaid sales tax at 14.5% per year or the commissioner’s underpayment rate, whichever is greater, running from the original due date until you pay.⁷ For a business that’s been misusing certificates over several years, the combined tax, penalties, and interest can be devastating.

The takeaway when filling out the form: match every field to reality. Your Certificate of Authority number, your actual business description, and the actual goods you’re buying to resell. If any of those don’t line up, the ST-120 is the wrong tool for the purchase.

1
Department of Taxation and Finance. Exemption Certificates for Sales Tax – Tax Bulletin ST-240
2
Department of Taxation and Finance. Register as a Sales Tax Vendor
3
Department of Taxation and Finance. How to Register for New York State Sales Tax – Tax Bulletin ST-360
4
New York State Senate. New York Tax Law 1105
5
Department of Taxation and Finance. Form ST-120 Resale Certificate
6
Legal Information Institute. New York Codes, Rules, and Regulations Title 20 532.4 – Presumption of Taxability
7
New York State Senate. New York Tax Law 1145 – Penalties and Interest