Before you start

Illinois residency
Proof of identity, residency and Social Security number, or TVDL-route documents
All out-of-state licences and IDs, for surrender
A registered, insured vehicle if a road test is required

Step-by-step

1
Decide whether you need to drive
Chicago has the second-largest rail transit system in the country on a flat, legible grid, plus an 18-mile lakefront cycle path. Between the L, buses and winter parking rules, going car-free here is genuinely common. Weigh that before spending the time.
OnlineWho: You
2
Do not rely on an International Driving Permit
Illinois explicitly does not recognise the IDP. The state suggests carrying one only so your home licence is translated into English. Anyone who told you an IDP substitutes for a licence here was wrong.
OnlineWho: You
3
Book a driver services facility appointment
Illinois Secretary of State facilities work by appointment and Chicago locations are busy. Ninety days is comfortable if you book on arrival, tight if you leave it.
OnlineWho: You
4
Bring every out-of-state licence and ID to surrender
Illinois will not issue until you hand over all other US state licences and ID cards. This is a hard requirement, applied at the counter, and forgetting means rebooking.
In personWho: You
5
Take the vision screening and the required tests
A vision screening is universal. Most new residents also take the written test and, depending on circumstances, a road test. If you take a road test you must supply a registered, insured vehicle.
In personWho: You
6
Learn winter parking rules before December
Chicago bans overnight parking on designated snow routes from 1 December to 1 April regardless of whether it has snowed, and imposes further bans once accumulation reaches two inches. Tow and fine costs are substantial. Check whether your street is a snow route the week you move in.
In personWho: You

Documents you’ll need

Foreign driver licence
Passport, visa and I-94
Social Security card, or TVDL-route documentation
Proof of Illinois residency
All out-of-state licences and ID cards, for surrender

Things most newcomers don’t know

Illinois does not recognise the International Driving Permit — at all.

This contradicts advice given by many countries' motoring associations, who sell IDPs on the basis that they are widely recognised in the US. Illinois says plainly that it does not recognise it and recommends one only as an English translation of your home licence. If you were relying on an IDP as your legal basis for driving here after 90 days, you have no legal basis.

Source: Illinois Secretary of State — driver's license FAQ

The 1 December to 1 April overnight ban applies whether or not it snows.

Chicago's winter overnight parking ban on designated snow routes runs on the calendar, not the weather. Cars are towed on clear, dry December nights every year by people who assumed the rule was conditional. A separate two-inch ban layers on top of it on other streets.

Source: City of Chicago — winter parking restrictions

Dibs is not law but it is enforced.

After a heavy snow, residents who dig out a street space mark it with chairs or crates and expect it to be respected. The city periodically clears the furniture and periodically ignores it. Taking a marked spot reliably produces retaliation. Whatever you think of the custom, understand it before your first big snow.

Source: community-reported

The city vehicle sticker is a separate annual obligation.

Chicago requires residents who own a vehicle to buy a city sticker on top of state registration, with late penalties. Newcomers routinely register with the state, assume they are done, and collect a ticket. If your street is permit-only you need a permit as well.

Source: City of Chicago — city vehicle sticker

Common mistakes to avoid

Relying on an International Driving Permit, which Illinois does not recognise.
Arriving at the facility without every out-of-state licence and ID to surrender.
Parking overnight on a snow route in December on a clear night.
Registering with the state and forgetting the Chicago city vehicle sticker.
Buying a car at all before checking whether your commute is a straightforward L ride.

Some of this may be out of date. Spotted something inaccurate? Help us keep it right for the next newcomer.