Design Firms
Design Firms

All Firms Must Register

All employers doing engineering design work in Illinois - even if based outside of Illinois - MUST register as a Design Firm.  The only exception to this rule is a sole proprietorship doing business in the EXACT name as is shown on the Illinois PE License.  In that case the sole proprietor may only offer services for which he/she is licensed.

Register to do Business with the State of Illinois

Authority to transact business in Illinois must be obtained before a firm can register as a Design Firm in Illinois - a requirement to legally do any design work in the state. Business registration in the State of Illinois is managed by the Secretary of State.   To register, go to the homepage at and click on "Business" from the homepage.    You may also try calling (217) 782-7880 or (312) 793-3380.

Must have Unique Managing Agent

All design firms must have at least one managing agent in charge of professional engineering services.  The managing agent must be a licensed professional engineer by the State of Illinois and may only be the managing agent for one company or firm.

Be sure to note that the organization must notify the Division of Professional Regulation within 10 business days if there is a change in managing agent.

Articles of Incorporation Purpose

As part of a design firm's application for registration, the organization's Articles of Incorporation must be submitted.  The "purpose" clause of those Articles must include the type of design service(s) the organization is seeking to offer in Illinois. 

Design Firm Seal

In addition to the professional engineer seal, all documents or technical submissions prepared by the design firm shall contain the design firm registration number issued by the department.