A proposal may be revoked at any time before the communication of its acceptance is complete as against the proposer, but not afterwards.
An acceptance may be revoked at any time before the communication of the acceptance is complete as against the acceptor, but not afterwards.
Illustration
A proposes, by a letter sent by post, to sell his house to B.
B accepts the proposal by a letter sent by post.
A may revoke his proposal at any time before or at the moment when B posts his letter of acceptance, but not afterwards.
B may revoke his acceptance at any time before or at the moment when the letter communicating it reaches A, but not afterwards.
STATE AMENDMENT
Uttar Pradesh.—

Amendment of section 5 of Act (9 of 1872).—In section 5 of Indian contract Act, 1872, hereinafter in this Chapter referred to as the principal Act, at the end of the first paragraph, the following explanation shall inserted, namely:—
"Explanation—Where an invitation to a proposal contains a condition that any proposal made in response to such invitation shall be kept open for a specified time and a proposal is thereupon made accepting such condition, such proposal may not be revoked within such time."
[Vide Uttar Pradesh Act, 57 of 1976, s. 2]