Illinois Used Car Sales Tax: Dealer Rate vs RUT-50 Flat Tax (2026)

Illinois taxes a used car two different ways, and the rules below are current as of Oct 19, 2026. Buy from a dealer and you pay a percentage, the 6.25% state rate plus local taxes, on the price after your trade-in. Buy from a private seller and you pay a flat amount on Form RUT-50 that depends on the car's age if it sold for under $15,000, or on the price if it sold for $15,000 or more. A 2016 car bought privately for $9,000 owes $115 to the state this year, and Chicago and Cook County can add more.

That flat private-party schedule is the part out-of-state buyers find strange, and it's also why people are tempted to write a lowball price on the paperwork. I read the Illinois Department of Revenue's RUT-5 chart for 2026, the RUT-50 instructions, the RUT-6 local guide and IDOR's vehicle tax FAQs on Monday, October 19, 2026. Everything below comes from those pages.

Dealer purchases: percentage tax, full trade-in credit

IDOR's private party page says sales by registered Illinois dealers are taxed under the Retailers' Occupation Tax Act, and its use tax rates page puts the state rate on general merchandise at 6.25%. Local taxes stack on top based on location, and the same page points to the MyTax Illinois Tax Rate Finder for looking up a specific address.

Trade-ins are where a lot of old advice is wrong. For dealer sales from Jan. 1, 2020, through Dec. 31, 2021, the trade-in credit for a passenger vehicle was capped at $10,000. IDOR's bulletin FY 2022-03 says Public Act 102-0353 removed that cap for sales on or after Jan. 1, 2022, so the full trade-in value now reduces the taxable price. I looked for a later law bringing the cap back and didn't find one. If a dealer tells you the trade credit tops out at $10,000, ask them to show you the current rule.

Private sales: the RUT-50 tables for 2026

The RUT-5 chart, effective Jan. 1 through Dec. 31, 2026, has two tables. Table A applies when the price, or fair market value, is under $15,000, and the tax depends on age:

• 2025 or newer: $465. 2024: $365. 2023: $290. 2022: $240.
• 2021: $190. 2020: $165. 2019: $155. 2018: $140.
• 2017: $125. 2016: $115. 2015 or older: $100.

Table B applies at $15,000 and up and goes by price: $850 for $15,000-$19,999.99, $1,100 up to $24,999.99, $1,350 up to $29,999.99, $1,600 up to $49,999.99, $2,600 up to $99,999.99, $5,100 up to $999,999.99, and $10,100 above that. The chart says outright that no trade-in deduction is allowed on this tax.

So the jump at $15,000 is real. A $14,900 private-sale 2020 car owes $165. Sell it for $15,000 and the tax becomes $850. Don't fake the price to stay under the line. When no price is stated, as with a gift or an even trade, fair market value is used, and IDOR's vehicle tax FAQs describe assessments that raise private-party tax based on fair market value. Your defense is a signed bill of sale or a licensed dealer's appraisal.

Family transfers, gifts and exemptions

The RUT-5 chart sets a $15 tax when the car is transferred or sold between spouses (including civil union partners), parents, brothers, sisters or children, adopted children included. Step-relatives, in-laws and grandparents or grandchildren don't qualify. The $15 rate also covers an estate gift to a beneficiary other than a surviving spouse and some business reorganizations. Tax is $0 for an estate gift to a surviving spouse, for tax-exempt organizations, and for an out-of-state resident who used the vehicle outside Illinois for at least three months. Motorcycles and ATVs are a flat $25.

Chicago and Cook County add their own amounts

Local private party taxes go on the same RUT-50, according to IDOR's RUT-6 reference guide. The version I pulled lists the City of Chicago at $80 for cars 3 years old or newer, $65 for 4 to 8 years, $50 for 9 to 14 years and $0 at 15 or older. Cook County is $225, $175 and $90 for the same kind of age bands, with the oldest band starting at 9 years. A Chicago address pays both. That RUT-6 is marked revised March 2024, so check it's still current before you budget.

Deadlines and moving in

RUT-50 is due within 30 days of buying the car, or within 30 days of bringing it into Illinois, and it's paid to the Secretary of State when you apply for title. If you bought from an out-of-state dealer that isn't registered with IDOR, the FAQ points you to Form RUT-25 instead. Our Illinois title transfer guide covers the Secretary of State side, and the general used car sales tax post compares states.

What the tax form won't tell you

The state doesn't care whether the car was flooded, rolled back or rebuilt. You should. Search the VIN on NMVTIS, and for salt-belt cars read our Illinois rust belt CARFAX tips. We're a licensed CARFAX and AutoCheck reseller and aren't affiliated with CARFAX, AutoCheck or Experian. In mid October 2026, our guest price was about $5.50 a report, members paid about $4.50, and the bundle ran about $6.75, versus roughly $39.99 to $44.99 retail. Confirm the total when you check out.