There isn't one.
ZIP +4 codes, the 9 digit ones, are for specific small areas (typically a block, a group of apartments, or even an individual high-volume receiver of mail), not something the size of a city. Rockford IL has several 5 digit ZIP codes, and each of these has many ZIP+4 codes within it.
Rockford IL possible zip codes. * ZIP Code 61101 * ZIP Code 61102 * ZIP Code 61103 * ZIP Code 61104 * ZIP Code 61105 * ZIP Code 61106 * ZIP Code 61107 * ZIP Code 61108 * ZIP Code 61109 * ZIP Code 61110 * ZIP Code 61112 * ZIP Code 61114 * ZIP Code 61125 * ZIP Code 61126
60126-4232
You will need to provide a specific address. A five-digit ZIP code typically contains hundreds or thousands of ZIP+4 codes, as that is the whole point of ZIP+4 codes.
Downers Grove, IL has two 5 digit Zip Codes 60515 and 60516.The additional 4 digits specify a specific location, residence, business, or P.O. Box within the primary Zip Code area. So there can be up to 20000 different valid 9 digit Zip Codes for Downers Grove, IL.
The zip code for Makanda, IL, is 62958.
From www.usps.com; 60622-7242
The Hanover Park, IL zip code is 60133. The zip code previously was 60103 (shared with Bartlett, IL) before 60133 was assigned to Hanover Park.
The zip codes for Bowlingbrook, IL are: * 60440 * 60490
Salem, IL's zip code is: 62881
The zip code for Belvidere, IL is 61008.
61455
60422