If the Illinois leasing company, lending agency, or other retailer is registered with the Illinois Department of Revenue to collect Illinois tax, then
Form ST-556 is used to report the purchase. Generally, the leasing company, lending agency, or retailer will complete and file this tax return along with the required title forms for you. If this is a transaction for lease, the registered retailer will complete
Form ST-556-LSE instead.
If the Illinois leasing company, lending agency, or retailer is not registered, you will be required to report your purchase. To do so, you must use
Form RUT-25. Since Form RUT-25 is due no later than 30 days after the date the vehicle is brought into Illinois and you already have possession of the vehicle in Illinois, use the actual purchase date for both the "purchase date" and the "date brought into Illinois" on the return. You should attach a copy of the bill of sale as proof of the purchase price. If this is a transaction for lease, you will complete
Form RUT-25-LSE instead. Attach a copy of the bill of sale or lease contract, as appropriate, as proof of the selling price and of any tax previously paid. If you cannot obtain the proper documentation, you may submit a letter from the leasing company or selling dealer.