What does 'irrevocable until' mean on my Ontario offer?

The "irrevocable until" clause in an Ontario offer is the deadline by which the seller must accept, reject, or counter-sign your offer. During that window, you as the buyer cannot withdraw or change your offer — it is locked in. If the seller does not respond before the stated date and time, the offer expires automatically and you are released.

The practical effect is that you are bound for a period even if circumstances change. If your financing falls through before the irrevocability period ends, or if you change your mind, you cannot simply walk away without risk. This is one reason buyers should ensure any conditions they need — such as financing or home inspection — are built into the offer rather than assumed.

Once the deadline passes without acceptance, you are free to submit offers elsewhere, adjust your price, or walk away entirely. If the seller accepts before the deadline, you have a binding contract. Understanding this clause is fundamental to reading any offer you sign — ask your lawyer or agent to walk you through it before submission.