In addition to the Illinois vehicle bill of sale, there are multiple other documents that are required such as the odometer disclosure statement and the seller’s report of sale (VSD-703). The seller's report must be submitted by them to the SOS right after the sale while the bill of sale is submitted by the buyer when registering.
Illinois has a relatively short time frame for registering a vehicle when it was purchased privately, given as a gift, or received as an inheritance. The registration process should be completed within twenty days of the original transactions. If you’re an individual buying a vehicle privately - not via a dealership - then you’re responsible for handling all of the paperwork associated with registering said vehicle.
Like other states, the registration must be renewed annually but it can be done online through the Secretary of State Vehicle Services Division webpage.
A duly completed and signed motor vehicle bill of sale form
An odometer disclosure statement for the vehicle if it’s under 20 years old and less than 16,000 pounds.
A completed application for vehicle transfer (VSD 190). It can be filled online but must be submitted within 7 days to a local SOS office.
A signed (by the previous owner) certificate of title
A form called the seller's report of sale (VSD-703)
A drivers license that’s valid in Illinois
Tax RUT-50
The fees associated with registration which are usually around $150
Valid proof of car insurance
If someone is registering the vehicle on behalf of the owner then a motor vehicle power of attorney is also required