Format guide
Illinois address format (IL)
Addresses in Illinois use the USPS abbreviation IL. Write the street number and street name on the first line, then Chicago, IL and a 5-digit ZIP on the last line. Apartment or suite numbers belong on their own line with Apt, Ste, or Unit.
Postal codes
Illinois ZIP codes are 5 digits and may include ZIP+4. Samples on this page stay in IL and use Chicago as the default city so form tests can check state, city, and postal fields together.
Typical use cases
Use this Illinois generator for layout and validation tests only. Do not submit the sample to payments, identity checks, shipping, or tax systems.
How to use test data
In development you can use these samples to check field length, line breaks, international characters, and responsive layouts. For payment, identity, logistics, or compliance flows, use official sandbox data from your provider—do not submit these samples to live systems.