The Texas Standard Presumptive Value is the state’s benchmark price for a used vehicle, and when you buy from a private party the county tax assessor-collector uses it to make sure you pay enough sales tax. The office compares what you paid against 80 percent of the vehicle’s SPV and charges 6.25 percent motor vehicle sales tax on whichever number is higher.1Texas Administrative Code. 34 Texas Admin Code 3.79 – Standard Presumptive Value The rule exists to stop buyers and sellers from writing an artificially low price on a bill of sale to shrink the tax bill.
How the 80 Percent Rule Works
Picture a used truck with an SPV of $15,000. Eighty percent of that figure is $12,000, and that number becomes the floor for your taxable value.
If you paid $13,000, the county taxes you on $13,000 because your price sits above the floor. If you paid $9,000, the county ignores the bill of sale and taxes you on $12,000 instead. Either way, the rate is a flat 6.25 percent. Texas does not stack local sales taxes on top of motor vehicle sales tax the way it does with store purchases.2Texas Comptroller of Public Accounts. Motor Vehicle – Sales and Use Tax
The only way to pay tax on a figure below 80 percent of SPV is to produce a certified appraisal showing the vehicle is genuinely worth less. That process has its own rules and a tight deadline, covered below.
Looking Up a Vehicle’s SPV Before You Buy
The Texas Department of Motor Vehicles publishes an online SPV calculator. Enter the Vehicle Identification Number and the odometer reading and it returns the current value; motorcycles don’t require an odometer reading.3Texas Department of Motor Vehicles. Standard Presumptive Values The figure the calculator gives you is the same figure the county clerk will see, so checking it before you hand over money lets you estimate the tax and avoid a surprise at the counter.
TxDMV sets the values using data from Black Book, drawn from Texas sales activity, and refreshes them at least quarterly. If the calculator returns no value — common with older, rare, or heavily modified vehicles — the county falls back on your actual purchase price to calculate tax.3Texas Department of Motor Vehicles. Standard Presumptive Values
When SPV Doesn’t Apply
SPV governs private-party sales, meaning any transaction in which neither party is a licensed dealer. Buy from a coworker, an online seller, or a private seller in another state who ships the vehicle into Texas, and SPV sets the floor. Several other situations sit outside the rule:1Texas Administrative Code. 34 Texas Admin Code 3.79 – Standard Presumptive Value
- Purchases from a licensed Texas dealer, where tax is based on the actual sales price and the dealer collects it directly.3Texas Department of Motor Vehicles. Standard Presumptive Values
- Even trades of vehicles between two owners, which carry a flat $5 fee.2Texas Comptroller of Public Accounts. Motor Vehicle – Sales and Use Tax
- Gifts between qualifying family members, which carry only a $10 gift tax.
- Vehicles inherited through an estate or a right-of-survivorship agreement, which as of September 1, 2025 are exempt from motor vehicle tax entirely.4Texas Comptroller of Public Accounts. Inherited Motor Vehicles – Motor Vehicle Tax Guide
- Vehicles eligible for a classic motor vehicle specialty license plate under the Transportation Code.
- Vehicles bought from any federal, state, county, or city government agency, including at public auction.
- Vehicles acquired through a mechanic’s lien or a storage facility lien.
- Vehicles acquired under state abandoned-vehicle procedures.
Which Family Gifts Qualify
The $10 gift tax is limited to transfers between specific relatives: a spouse (when the vehicle is separate property), a parent or stepparent, a child or stepchild, an in-law in the parent-child line, a grandparent or grandchild (including great- and in-law equivalents), a sibling or sibling-in-law, and a legal guardian.5Texas Comptroller of Public Accounts. Family Transfers – Motor Vehicle Tax Guide Cousins, aunts, uncles, and friends are not on the list, so a transfer to any of them is treated as an ordinary private-party sale with SPV in play. And the gift has to be a true gift. If any money changes hands, the transaction becomes a sale and SPV applies.
Overriding the SPV With a Certified Appraisal
SPV doesn’t account for condition. A car with a blown transmission, hail damage, or a quarter-million miles may genuinely be worth less than 80 percent of the guide value, and Texas lets you prove it with a certified appraisal on Comptroller Form 14-128, the Used Motor Vehicle Certified Appraisal Form.6Texas Comptroller of Public Accounts. Used Motor Vehicle Certified Appraisal Form
Only two kinds of professionals can complete the form: a licensed Texas motor vehicle dealer or a licensed insurance adjuster.7Texas Comptroller of Public Accounts. Motor Vehicle Tax Guide – Valid Certified Appraisal A dealer can appraise only the category of vehicle their license covers, so an automobile dealer cannot appraise a motorcycle. Insurance adjusters can appraise any used vehicle. The appraiser must physically inspect the vehicle, fill in every field on the form (VIN, odometer, appraiser’s name, business address, state license number), state a value that reflects actual condition, and sign to certify it.6Texas Comptroller of Public Accounts. Used Motor Vehicle Certified Appraisal Form
Dealers are bound by the fee schedule in Rule 3.79; insurance adjusters set their own rates.8Texas Comptroller of Public Accounts. Private-Party Purchases and Standard Presumptive Values Most standard appraisals run roughly $50 to $200, more for specialty vehicles. Compare the appraisal fee to the tax savings before paying for one.
The 20-Day Deadline
You have 20 county working days from the purchase date to obtain the certified appraisal. If you bought the vehicle out of state, the clock starts the day it enters Texas, not the day you paid for it.1Texas Administrative Code. 34 Texas Admin Code 3.79 – Standard Presumptive Value Working days exclude weekends and county holidays, so 20 working days works out to around four calendar weeks.
Miss it and the county will tax you on the higher of your purchase price or 80 percent of SPV with no appraisal accepted. There is no extension and no appeal, so book the appraisal as soon as the sale closes.
Paying the Tax on Time
You have 30 days from the purchase date to pay the motor vehicle sales tax at your county tax assessor-collector’s office. Active-duty military members get 60 days. After that the penalties start:9Texas Comptroller of Public Accounts. Penalty on Late Tax Payment – Motor Vehicle Tax Guide
- On day 31 (or day 61 for military), a 5 percent penalty is added to the tax owed.
- On day 61 (or day 91 for military), another 5 percent is added, taking the total penalty to 10 percent.
The minimum penalty is $1. County offices have no authority to waive it, so a slow seller, a long line at the tax office, or missing paperwork will not get you off the hook.9Texas Comptroller of Public Accounts. Penalty on Late Tax Payment – Motor Vehicle Tax Guide Exempt transfers, even trades, and $10 gift transfers are not subject to these late penalties.