Is a purchase agreement valid if only one spouse signed it without consent to sell the matrimonial home?

Generally, an Agreement of Purchase and Sale for a matrimonial home signed by only the titled spouse, without the other spouse's required consent, isn't automatically void from the start — it's better understood as vulnerable to being set aside at the request of the spouse who didn't consent, since the Family Law Act's protection exists specifically for that spouse's benefit. This distinction matters because it affects who can challenge the transaction and what happens to a buyer who wasn't aware of the problem.

A purchaser who dealt in good faith, without knowledge that spousal consent was required and missing, and who relied on a proper statutory declaration from the selling spouse about their marital status, may be protected from having the sale unwound, even if consent should have been obtained. This is precisely why lawyers routinely require a spousal consent or a statutory declaration confirming marital status before closing — it's the mechanism that protects both the non-consenting spouse's rights and an innocent buyer's interests. Anyone who discovers a sale went ahead without proper spousal consent, on either side of the transaction, should get legal advice quickly, since remedies and time matter in these situations.