35 ILCS 158/15-15: Rate of tax.

The rate of tax is 6.25% of the purchase price for each purchase of watercraft that is subject to tax under this Law. When an ownership share of a watercraft is acquired, the tax is imposed on the purchase price of that share. All owners are jointly and severally liable for any tax due as a result of the purchase, gift, or transfer of an ownership share of the watercraft.