How to Fill Out Indiana Form ST-105: Sales Tax Exemption Certificate

Indiana Form ST-105, officially State Form 49065, is the Indiana Department of Revenue’s general sales tax exemption certificate. You fill it out and give it to a seller to document that your purchase is exempt from Indiana’s 7% sales tax.¹ The form is sometimes misidentified as “State Form 49465,” but the correct number printed on the certificate is 49065.² A fillable PDF is available on the Department of Revenue’s sales tax forms page.³

The form is not mailed to the state. You hand it directly to the seller, who keeps it on file as proof that the sale was properly made without tax.

Who Qualifies to Use Form ST-105

The ST-105 covers several exemption categories, and you check only the one that applies to your purchase in Section 4. The reasons listed on the certificate are:²

Resale — retailers, wholesalers, or manufacturers buying items solely to resell them in the ordinary course of business.
Manufacturing machinery, tools, and equipment used directly in direct production, manufacture, fabrication, assembly, processing, refining, or finishing of tangible personal property.⁴
Public transportation property used more than 50% in providing public transportation (you must list your USDOT number).
Agricultural production — machinery, tools, and equipment used directly in producing agricultural commodities for sale by someone occupationally engaged as a farmer.⁵
Contractor purchases of materials for projects benefiting public schools, government entities, or nonprofits.
Indiana governmental units — state agencies, cities, towns, municipalities, public schools, and state universities.
U.S. federal government agencies (the agency name must appear on the form).
Other — a catch-all where you must write the specific statutory basis for the exemption.

Nonprofits that are organized and operated exclusively for religious, charitable, scientific, literary, educational, or civic purposes, with no income benefiting any private member, trustee, or employee, also qualify.⁶

The ST-105 does not cover purchases of utilities, vehicles, watercraft, or aircraft. Those categories have separate exemption processes and should not be claimed on this form.²

How to Fill Out Form ST-105

The form has five sections, and all of them must be completed. If any section is left blank, the certificate is invalid, and the seller becomes responsible for collecting the 7% sales tax on the transaction.²

Section 1: Purchaser Identification

Enter your Indiana Taxpayer Identification Number (TID), a ten-digit number, followed by your three-digit location (LOC) number. Both appear at the top right of your Registered Retail Merchant Certificate. The TID is the same number as your Sales Tax ID, Withholding Tax ID, or Tax Exempt ID issued by the Indiana Department of Revenue.²

If you don’t have an Indiana TID, the form allows alternatives:²

Out-of-state purchasers can use a business license number or state-issued ID from their home state.
Federal agencies enter their Federal Identification Number (FID).
Farmers without a state business license may enter a Social Security number or FID.
Public transportation haulers operating under someone else’s motor carrier authority, and contracted school bus operators, may also use an SSN or FID.

Section 2: Seller Information

Enter the seller’s name and business address. This ties the certificate to a specific vendor relationship.

Section 3: Purchase Type and Description

Check one of two boxes: single purchase or blanket exemption. A single-purchase certificate covers only the transaction described on the form. A blanket certificate covers all future qualifying purchases from the same vendor. Then describe the products you’re buying. For a blanket certificate, a general description of the product category is enough; you do not need to list every future item.

Section 4: Reason for Exemption

Check the one box that matches your exemption category from the list above. If you check “Other,” write a brief explanation of the specific statutory exemption that applies. Only one reason per certificate.

Section 5: Signature

Sign and date the form, and print your name and title. The signature is a legal certification under penalties of perjury that the purchase qualifies for the exemption you claimed and that the item is not a utility, vehicle, watercraft, or aircraft.²

An Extra Step for Farmers

If you’re claiming the agricultural equipment exemption, you should first complete the Agricultural Equipment Exemption Usage Questionnaire (Form AGQ-100) to determine how much of the purchase qualifies. If the equipment is used predominantly (more than 50%) for exempt agricultural purposes, the entire purchase is exempt.⁵ If it doesn’t qualify for a full or predominant-use exemption, don’t give the ST-105 to the seller. Pay the sales tax at purchase and then file a Claim for Refund (Form GA-110L) with the Department of Revenue, attaching your completed AGQ-100.²

Single Purchase or Blanket Certificate

A single-purchase certificate is one form, one transaction. A blanket certificate is more practical if you buy from the same vendor regularly: once filed, every qualifying purchase from that seller is covered without new paperwork each time. Indiana blanket certificates have no printed expiration date and remain valid as long as the information stays accurate and your exempt status is unchanged. The Department of Revenue recommends reviewing blanket certificates every few years and updating them if your business name, address, TID, or exemption status changes.

What Happens After You Give the Form to the Seller

Present the completed, signed ST-105 to the seller at or before the time of purchase so the 7% sales tax is left off the invoice. Under Indiana law, any purchase delivered in Indiana is presumed taxable unless the seller has an exemption certificate on file.⁷ The certificate is the seller’s proof that they properly didn’t collect tax.

Sellers must keep each exemption certificate on file.² Indiana’s general record-retention rule requires keeping tax records for at least three years after the final payment of the tax liability was due. If an audit is underway or the Department of Revenue extends the assessment period beyond three years, records must be kept until the process concludes.⁸

Consequences of Misusing the Certificate

The signature line includes an acknowledgment that misuse of the certificate, whether negligent or intentional, can result in unpaid tax, interest, and civil or criminal penalties against both the individual signer and the business entity they represent.² The Department of Revenue audits sellers’ files and traces exemption certificates back to the purchaser. If a purchase didn’t actually qualify, liability shifts to the buyer.

A common way people cross that line is buying something tax-free for resale and then pulling it from inventory for personal or business use. When that happens, the item is no longer exempt, and use tax is owed. The Department of Revenue specifically identifies items withdrawn from inventory for personal use or giveaways as a trigger for use tax liability.⁹ Use tax is the same 7% rate as sales tax and is reported on your regular Indiana sales and use tax return for the period when you first used or consumed the item.

An Alternative: The Streamlined Sales Tax Certificate

Indiana is a member of the Streamlined Sales and Use Tax Agreement, so sellers in Indiana also accept the multi-state Streamlined Sales Tax Exemption Certificate in place of the ST-105. If you buy from vendors in multiple states, one certificate format can work across all 24 member states instead of a different form for each. When you use the Streamlined certificate in Indiana, you still provide your Indiana TID if the exemption requires state registration; if you aren’t registered in Indiana, you can enter a sales tax ID from any state, including your Streamlined registration ID (SSTID).¹⁰

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Indiana Department of Revenue. Sales Tax
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Indiana Department of Revenue. General Sales Tax Exemption Certificate Form ST-105
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Indiana Department of Revenue. Sales Tax Forms
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Indiana General Assembly. Indiana Code 6-2.5-5-3 – Exemption; Acquisition for Direct Use in Direct Production
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Indiana General Assembly. Indiana Code 6-2.5-5-2 – Agricultural Machinery, Tools, and Equipment
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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 6-2.5-3-7 – Presumption of Taxability; Exemption Certificate
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Indiana General Assembly. Indiana Code 6-8.1-5-4 – Record Keeping Requirements
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Indiana Department of Revenue. Business FAQ
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Streamlined Sales Tax Governing Board. Exemptions