Short answer: Yes you must have a permit.
Depending on the type of animal and purpose of having the animal, the permit one needs varies. I believe one needs a "Fur Bearing Mammal Breeder/Possession Permit" to own a raccoon. Class A permits are for possessing protected animals when you do not intend to sell them (i.e. non-commercial use) and these are $10, Class B permits are for possession protected animals when you do intend to sell them (i.e. commercial) and are $20, and Fur Bearing Mammal permits are for possessing and selling fur bearing mammals, which includes a raccoon, and I did not see the fee on these.
Also, the animal must have been obtained from a licensed breeder to get a permit to legally own it. One cannot trap or catch a raccoon and then get a permit to own it.
Long answer: Click on any of the statutes below if you want to view the statute.
Illinois Compiled Statute 520 ILCS 5/1.2g defines a raccoon as one of the animals deemed a "furbearing mammal" for code reference purposes.
Illinois Compiled Statute 520 ILCS 5/2.2 says that "It shall be unlawful for any person at any time to take, possess, sell, or offer for sale, any of these wild birds (dead or alive) and parts of wild birds (including their nests and eggs), wild mammals (dead or alive) and parts of wild mammals, including their green hides contrary to the provisions of this Act," and the Act specifically lists raccoons among those animals covered by the Act. The Act goes on to say that bona-fide public or state scientific, educational or zoological institutions can have these animals though if the animals were salvaged or legally obtained.
So, you have to comply with the Act to own a raccoon.
Illinois Compiled Statute 520 ILCS 5/3.23 says that "Before any person shall hold, possess or engage in the raising of game mammals, game birds or migratory game birds protected by this Act, he shall procure a permit from the Department to do so. Any person desiring to possess, propagate, hold in captivity but not offer for sale any species protected by this Act may do so by acquiring either a Class A Noncommercial bird breeders permit or a Class A Noncommercial game breeders permit. Any person desiring to possess, propagate, to hold in captivity, to sell alive, for propagation or hunting purposes, sell dressed for food purposes any species protected by this Act may do so by acquiring a Class B Commercial bird breeders permit or a Class B Commercial/game breeders permit."
So, a permit is required, and different permits are needed for different purposes.
Also of note is Illinois Compiled Statute 520 ILCS 5/2.30 says that you can only trap or hunt raccoons during the appropriate season. However, you cannot trap a raccoon and then apply for a permit, you can only get a permit to possess a raccoon if you got the raccoon from another permitted owner.
You can view the Illinois Department of Natural Resources website here. A link to the Illinois DNR page discussing permits and licenses is here. A link to the Class A and Class B wild game permits is here, and a link to the fur bearing mammal permit is here (pdf format). A link to the fur bearing mammal permit is here (pdf format).
I hope this helps and a positive feedback is always appreciated if this was useful to you.
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