Irrevocable period

The irrevocable period is the window during which a signed offer stays open for acceptance and cannot be revoked by the party who made it. On Ontario’s standard forms it’s a filled-in blank — “irrevocable until 9:00 p.m. on the 14th” — and it converts an offer from a casual proposal into a firm one: until that moment, the other side holds an exclusive option to create a binding contract simply by accepting and communicating it.

The mechanics

Ordinary contract law lets an offeror withdraw any time before acceptance. The irrevocability clause deliberately gives that right away, under seal, so the recipient can deliberate without the offer evaporating mid-thought. Three consequences follow. Acceptance — signed and communicated back — before the deadline forms a binding agreement of purchase and sale; what was communicated a minute late forms nothing. A counter-offer kills the original and starts a new irrevocable clock, this time binding the counter-offering side. And until expiry, the offering party is stuck: spotting a better house an hour after submitting does not un-sign the offer.

The strategy hiding in a time field

Agents fight over this blank for good reason. A short window — hours — protects a buyer in competition, because every extra hour is time for the listing side to use your offer as leverage to extract a richer one from someone else. A longer window suits offers made into silence: an out-of-town seller, an estate, a property sitting quiet, where you genuinely want an unhurried decision rather than a reflexive rejection. Sellers play the same game on counter-offers, often keeping their own irrevocable short so they aren’t locked up if another buyer surfaces. In multiple-offer situations, presentation timing and irrevocable deadlines interact — an offer engineered to expire before the scheduled offer night forces the seller to choose between dealing with it now and letting it die.

Details that catch people

The deadline is exact — date and time — and disputes about whether acceptance was communicated in time are why agents confirm delivery in writing rather than by vibes. The clause binds the maker even against events like a competing accepted offer elsewhere; serious buyers avoid holding two live offers at once. And an expired offer isn’t revived by goodwill: any post-deadline “yes” is a fresh offer, with all terms back on the table.