(810 ILCS 5/2-209)
(from Ch. 26, par. 2-209)
Modification, rescission and waiver.
(1) An agreement modifying a contract within this Article needs no
consideration to be binding.
(2) A signed agreement which excludes modification or rescission except
by a signed writing cannot be otherwise modified or rescinded, but except
as between merchants such a requirement on a form supplied by the merchant
must be separately signed by the other party.
(3) The requirements of the statute of frauds section of this Article
(Section 2-201) must be satisfied if the contract as modified is within
(4) Although an attempt at modification or rescission does not satisfy
the requirements of subsection (2) or (3) it can operate as a waiver.
(5) A party who has made a waiver affecting an executory portion of the
contract may retract the waiver by reasonable notification received by the
other party that strict performance will be required of any term waived,
unless the retraction would be unjust in view of a material change of
position in reliance on the waiver.
(Source: Laws 1961, 1st SS., p. 7