How Do I Get an Indiana Sales Tax Exemption Certificate?

To get an Indiana sales tax exemption certificate, a business fills out Form ST-105 and hands it to the seller at the time of purchase; a qualifying nonprofit registers with the Indiana Department of Revenue by filing Form NP-20A through the state’s online portal, INTIME, and receives Form NP-1 as its official exempt-status document.¹² The certificate lets you skip Indiana’s seven percent sales tax on purchases that qualify under state law.

Who Can Claim the Exemption

Indiana Code Title 6, Article 2.5, Chapter 5 sets out the categories of exempt transactions.³ The most common are:

Resale by retailers, wholesalers, and manufacturers buying tangible personal property they intend to resell in the ordinary course of business.
Manufacturing purchases of machinery, tools, and equipment used directly in the direct production of other tangible personal property.
Agricultural purchases by farmers of items used directly in producing agricultural products for sale.
Purchases by Indiana governmental units (state agencies, cities, towns, public schools, state universities) and the federal government.
Qualifying nonprofits buying property or services used to carry on their tax-exempt purpose.
Tangible personal property used predominantly (more than 50 percent) in providing public transportation.
Construction materials purchased by contractors working on projects for exempt entities such as public schools, government agencies, or nonprofits.

Each category matches a checkbox on Form ST-105, except for nonprofit purchases, which run through a separate registration.

Getting the Certificate as a Business: Form ST-105

Form ST-105 is the general sales tax exemption certificate for most exempt purchases in Indiana. Download it from the Department of Revenue’s sales tax forms page.⁴ The form has five sections.

Section 1, purchaser information. Enter your business name, address, and at least one identification number. If you hold an Indiana Registered Retail Merchant Certificate, enter your ten-digit Taxpayer Identification Number (TID) and three-digit location code (LOC) exactly as they appear on that certificate. If you are not registered in Indiana but hold a sales tax registration in another state, you can use that state’s tax ID number instead.⁵

Section 2, seller information. Enter the vendor’s name and address.

Section 3, purchase type. Check whether this is a blanket certificate or a single-purchase certificate, and describe the items being purchased.

Section 4, exemption category. Check the box that matches your reason for claiming the exemption: resale, manufacturing, agriculture, government purchase, contractor for an exempt project, public transportation, or “Other” with an explanation.

Section 5, signature. Sign, print your name, add your title, and date the form.

If you plan to make exempt purchases from Indiana vendors, the standard approach is to register for a Registered Retail Merchant Certificate ($25 per business location) and use its TID and LOC on your ST-105.⁶ Note that since January 1, 2023, nonprofits and purchasers of gasoline from fuel distributors no longer use ST-105 for those exemptions. Separate forms apply.⁴

Getting the Certificate as a Nonprofit

A nonprofit does not simply hand a vendor an ST-105. It must first register with the Department of Revenue by filing Form NP-20A through INTIME at intime.dor.in.gov. After the Department reviews and accepts the application, the organization receives Form NP-1, the official document confirming its exempt status, and can obtain its specially issued exemption certificate directly through INTIME.²⁷

To qualify under Indiana Code 6-2.5-5-25, the nonprofit must use the property or service to carry on, or to raise money to carry on, its tax-exempt purpose.⁸ Items bought for the private benefit of an individual, or for purposes unrelated to the organization’s mission, do not qualify. The statute covers a broad range of nonprofit types, including charitable organizations, educational institutions, religious organizations, fraternal groups, and affiliated agencies of united funds. If the organization’s exempt status is revoked or its mission changes significantly, a new application may be needed.

Blanket or Single-Purchase

Section 3 of Form ST-105 asks you to pick one. A blanket certificate covers every qualifying exempt purchase you make from the same vendor over time. Once it is on file, you do not present a new form for each transaction. Any purchase that falls within the exemption category you selected is covered. Indiana law authorizes the Department of Revenue to set conditions and restrictions on blanket certificates, including the kinds of purchases they cover.⁹

A single-purchase certificate applies to one specific transaction. Use it for occasional buys from a vendor you do not regularly work with, and include a clear description of the items so the vendor’s records show what was purchased tax-free.

Giving the Certificate to the Seller

Hand the completed, signed certificate to the seller at or before the time of purchase. The vendor keeps it on file as proof that the transaction was properly exempted. Indiana law presumes all retail sales are taxable, so the seller carries the burden of documentation justifying why no tax was collected on a given invoice.¹⁰

Give the vendor a new certificate any time your business address, TID number, or exemption category changes. Sellers are encouraged to verify the identification numbers you provide through state verification tools before accepting the form.

Keeping Records

Both buyers and sellers should keep copies of exemption certificates and related documentation for at least four years after filing, matching the statute of limitations for tax assessments under Indiana Code 6-8.1-5-2.¹⁰

If You Already Paid Sales Tax by Mistake

If you paid Indiana sales tax on a purchase that should have been exempt, you can claim a refund on Form GA-110L, filed electronically through INTIME or on paper.¹¹ Include a full explanation of why the refund is due, along with supporting documentation: invoices showing tax paid, copies of exemption certificates, proof of payment, and any other relevant records. Allow at least 60 days for processing. The sales tax belongs to the purchaser, not the vendor, so a vendor can only claim a refund if it has evidence it returned the tax to the customer.¹²

Buying Across State Lines

Indiana is a full member of the Streamlined Sales Tax (SST) agreement and accepts the SST Certificate of Exemption in addition to Form ST-105.¹⁰ The SST certificate is accepted by all 24 member states, which is useful if you buy from vendors in multiple states and want one standardized form.¹³

If you are an out-of-state business making exempt purchases from Indiana vendors, you can use the SST certificate or Form ST-105 with your home state’s tax ID number in place of an Indiana TID.⁵ Not every exemption available in Indiana applies in other states, and some states require state-specific identification numbers for certain exemption types, so confirm the rules with each state where you plan to claim an exemption.

1
Indiana Department of Revenue. Sales Tax
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Indiana Department of Revenue. Nonprofit Tax Forms
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Indiana General Assembly. Indiana Code Title 6, Article 2.5, Chapter 5 – Exempt Transactions of Retail Merchant
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Indiana Department of Revenue. Sales Tax Forms
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Indiana Department of Revenue. General Sales Tax Exemption Certificate Form ST-105
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Indiana General Assembly. Indiana Code 6-2.5-8-1 – Registered Retail Merchants Certificate
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Indiana Department of Revenue. Sales Tax Information Bulletin 10 – Application of Sales Tax to Nonprofit Organizations
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Indiana General Assembly. Indiana Code 6-2.5-5-25 – Exemption, Nonprofit Organizations
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Indiana General Assembly. Indiana Code 6-2.5-8-8 – Exemption Certificates
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Indiana Department of Revenue. Audit Manual
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Indiana Department of Revenue. Sales and Use Tax Refunds
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Indiana Department of Revenue. Claim for Refund – Form GA-110L
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Streamlined Sales Tax. Exemptions