Sales tax on invoices in Oklahoma

Oklahoma treats contractors who improve real property as consumers or users. You pay sales tax on the materials, supplies and equipment you buy for the job, and you can buy tax-free for an exempt customer only in the cases the law lists.

Sales tax permit and who owes the tax

In Oklahoma, the vendor of merchandise, the performer of taxable services and the renter or lessor of property carry the primary burden of the sales tax: they collect it from the purchaser, user or consumer. A vendor that fails or refuses to collect it becomes liable for the tax itself and can be fined or imprisoned.

If you’ll regularly and continuously make taxable sales from an established place of business, you need a written sales tax permit from the Oklahoma Tax Commission before you start. It costs $20 and is renewed every three years.

Contractors: consumers of what they buy

Oklahoma defines contractors as consumers or users: they pay sales tax on all taxable services and tangible personal property, including materials, supplies and equipment, that they buy to develop, repair, alter, remodel and improve real property. The Tax Commission’s rules name painting, road, grading and excavating, electrical and plumbing contractors, and anyone else with a contractual arrangement to improve real property; a person working for a salary or wage isn’t a contractor.

• Exempt customers: you may buy tax-free on a customer’s exempt status only in the cases the statute lists. They include purchases necessary to carry out a public contract, or a subcontract under one, with an Oklahoma municipality, county, public school district, city-county library system, institution of the Oklahoma System of Higher Education or rural water district, and a construction contract with a church.
• SB 44, from November 1, 2026: sales of tangible personal property and services to contractors and subcontractors performing contracts with exempt entities under new subsection (B) of 68 O.S. § 1356 become exempt from state sales tax. To claim it, give the vendor the entity’s exemption certificate and proof of your contract with it.

Services: certain services only

Oklahoma’s sales tax applies to transfers of tangible personal property in the state and to certain services provided there. If you provide nontaxable services, the equipment, materials and supplies you buy, lease or rent for them are taxable to you, and your customer’s exempt status doesn’t pass through to you. Check with the Tax Commission whether a particular service you provide is taxable.

Adding the tax: required, and never advertise absorbing it

On a contract to improve real property, Oklahoma treats you as the consumer, and the tax is the one you pay on your materials when you buy them; the rules below are for a vendor’s taxable sales. An Oklahoma vendor must add the tax to the selling price or charge, and may not advertise or hold out in any way that it will absorb all or part of the tax or relieve the purchaser from paying it. Neither Oklahoma’s statutes nor the Tax Commission’s rules require you to state the price separately from the tax, though the rules call it desirable for accounting and auditing.

Tax collected as part of a tax-included price may be backed out of your total receipts to find the amount subject to tax. The burden of proving that you added and collected the tax is on you, and whether you did is decided as a question of fact, so keep books, records, price lists or signs that show it.

If you sell tangible personal property and install it, a lump-sum price for both, or billing and records that don’t show separate charges, makes your total receipts the measure of the tax. If you have a standard retail price for the item that you use both over the counter and when you install it, you may add a separate installation charge, which isn’t taxed when it’s shown separately in your billings and on your books.

Local tax: county, city and the point of delivery

Counties and municipalities levy sales taxes on top of the state rate on this page. A sale at your place of business is sourced there; when you deliver the product to your customer at another location, the rate where the customer receives it applies. The Tax Commission links a Sales and Use Tax Rate Locator for the rates.

Watch-out: repairing personal property

Oklahoma’s rules treat repairmen, meaning people in the business of repairing tangible personal property, as the consumers of the parts incidental to the repair service that they use up in making repairs, so those parts are taxable to them.