Illinois Used Car Buyer's Paperwork Checklist
Use this checklist to prepare for buying a used vehicle from a private seller in Illinois. Confirm the latest requirements with the Illinois Secretary of State — Vehicle Services before completing your transaction.
Quick answer
Illinois buyers must apply for title and registration at an Illinois Secretary of State facility within 20 days of purchase. Private party purchases generally require Form RUT-50 (Private Party Vehicle Tax Transaction) to document and pay the applicable use tax — check the Illinois Department of Revenue website for current rates. The seller retains their Illinois license plates, so plan to obtain new plates at registration.
Key facts
- State
- Illinois
- Agency
- Illinois Secretary of State
- Process
- Buy a Used Car
- Notary required
- No
- Bill of sale
- Conditional
- Odometer disclosure
- Yes
- Filing deadline
- 20 days
- Last verified
- 2026-05-10
- Official source
- Illinois Secretary of State ↗
Key facts from official sources
Form RUT-50 (Private Party Vehicle Tax Transaction) is generally required for private party purchases.
Illinois Department of Revenue — RUT-50 Private Party Vehicle Tax ↗Private party use tax generally applies to private party vehicle purchases in Illinois. Filed using Form RUT-50.
Illinois Department of Revenue — RUT-50 Private Party Vehicle Tax ↗Illinois generally does not require notarization to buy a used car from a private seller.
Illinois Secretary of State — Vehicle Services ↗Buyer must apply for title and registration at an IL SOS facility within 20 days of purchase.
Illinois Secretary of State — Title and Registration ↗Quick reference
Notary required?
✗NoBill of sale?
◆ConditionalOdometer disclosure?
✓YesInspection required?
?Verify⏱ Important Deadlines
- 20-day deadline: Apply for title and registration at an IL SOS facility within 20 days of purchaseOfficial source ↗
Buyer Checklist
Items the buyer typically needs to prepare or provide.
Required Forms
Fees
Title fee + registration fee + private party use tax (Form RUT-50)
Private party use tax applies at 6.25% or reduced rate for lower-priced vehicles. File Form RUT-50.
Special requirements
Illinois generally does not require notarization for private vehicle purchases.
Not required by law but strongly recommended as proof of purchase.
Seller must complete odometer disclosure on the title for vehicles under 10 years old.
Inspection requirements vary by state and vehicle type. Check your state agency.
Step-by-step process
- 1Verify seller's name matches title and check for outstanding liens.
- 2Seller signs back of title and completes odometer disclosure.
- 3Obtain a written bill of sale with VIN, price, date, and both parties' information.
- 4Complete Form RUT-50 (Private Party Vehicle Tax Transaction).
- 5Submit the signed title, RUT-50, proof of insurance, and fees to an Illinois SOS facility within 20 days.
- 6Obtain new Illinois plates — the seller keeps their plates.
Common mistakes to avoid
- ✗Missing the 20-day title transfer deadline.
- ✗Not filing Form RUT-50 — private party use tax is required in Illinois.
- ✗Forgetting that the seller keeps their Illinois plates — you need new plates.
- ✗Not verifying the title is free of liens before purchase.
Official links
Source verification
This page covers 5 researched claims about Illinois buy a used car:
Directly cited from official sources
Inferred — confirm with agency before acting
Researched from Illinois Secretary of State — Vehicle Services. Requirements can change — always verify with the official agency before submitting documents.
Frequently asked questions
How long do I have to register after buying a used car?
Deadlines vary by state. In Illinois, confirm the registration deadline with the Illinois Secretary of State — Vehicle Services to avoid late fees.
What if the title has errors?
Do not accept a title with correction fluid or scratched-out information. Ask the seller to obtain a corrected title from the DMV before completing the sale.
Can I drive the car home before registering it?
Many states offer a short window or allow a temporary permit. Check your state agency for guidance.
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Last reviewed: 2026-05-10 · Reviewed by the Car Paperwork editorial team · Based on official Illinois Secretary of State — Vehicle Services sources · Independent resource · Not legal advice