Vendor Registration

There are TWO separate processes for registration as a vendor in the City’s iSupplier Portal. It is important that your firm determines which process you should follow and that you read all the instructions below.

Existing City of Chicago Vendors

If your business has previously registered with the City, had a contract (excluding subcontracts) or received a payment from the City, your firm should follow the process directly below. The following are NOT included in this group:

  • Vendors who have only had contracts with Sister Agencies, as opposed to with the City of Chicago. Contracts with the following Sister Agencies would not qualify for previous registration with the City of Chicago:
    • Chicago City Colleges
    • Chicago Housing Authority
    • Chicago Park District
    • Chicago Public Schools
    • Chicago Transit Authority
    • Metropolitan Pier & Exposition Authority (MPEA)
    • Public Building Commission
  • Vendors who have done business only with Cook County, but not with the City.
In order to register your business in the City of Chicago iSupplier Portal, you will need to send an email to  with the subject “Request an iSupplier Invitation”, or click on the button below. Within two business days, you will receive an e-mail invitation from the City that provides a link to the iSupplier website and instructions for filling out and submitting your registration.




New Vendors with the City of Chicago

Vendors who have never previously registered with the City of Chicago, never received a payment from the City of Chicago or never had a contract with the City of Chicago should follow this process. Click the New Vendor Registration button below; it will take you to the registration page in the iSupplier Portal where you can complete the process.
If during registration you receive an error message stating that a supplier with the same name or the same FEIN number already exists, your business already has a City vendor number and you should follow the above “Registration for Existing City of Chicago Vendors” process.

How to Register


In either case, if more than one person at your business will use iSupplier, please add them as “contacts” and check “Create User Account For The Contact” next to each contact. This will create separate iSupplier login accounts for each user.