Common law name changes adopted in this State on or after July 1, 2010 are invalid. All name changes shall be made pursuant to marriage or other legal proceedings.
21-105.Invalidity of common law name changes.
Article XXI. Change of Name · Last amended 2010 · Last verified July 20, 2026
In one sentenceInvalidates any name change made informally, without a court proceeding or marriage, in Illinois on or after July 1, 2010.
Full Text of 735 ILCS 5/21-105
Plain-English Summary
Section 21-105 closes the door on informal name changes. Before this section, some people in Illinois changed their name by consistently using a new one — a so-called common-law name change, recognized in many states without any filing at all. This section says that any common-law name change adopted in Illinois on or after July 1, 2010, does not count.
From that date forward, a name change is only valid if it comes through marriage or another legal proceeding, meaning a court case like the one the rest of Article XXI sets out. The section does not reach back to undo name changes people made informally before the cutoff date; it only forecloses the informal route going forward.
Frequently Asked Questions
Can I still change my name in Illinois just by using a new one consistently?
No, not since July 1, 2010. Any common-law name change adopted on or after that date is invalid under Illinois law.
What counts as a valid way to change your name in Illinois now?
Marriage, or another legal proceeding — meaning a court case, typically the name-change petition process set out in the rest of Article XXI.
Does this section undo name changes made before July 1, 2010?
No. The section applies to common-law name changes adopted on or after that date; it does not speak to changes made earlier.
Why did Illinois eliminate common-law name changes?
The section itself does not state a reason, only the rule: common-law name changes adopted from July 1, 2010 onward are invalid, and all changes must go through marriage or a legal proceeding instead.
Does getting married still count as a valid way to change your name?
Yes. Marriage remains an express exception alongside formal legal proceedings.
Amendment History
(Source: P.A. 96-1231, eff. 7-23-10.)
Source & verification. Section text and amendment history are
reproduced verbatim from the Illinois Compiled Statutes, published by the
Illinois Compiled Statutes, Illinois General Assembly / Legislative Reference Bureau. Last verified July 20, 2026.
· Official source
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