Do both spouses need their own separate lawyer for a separation agreement in Ontario?

Both spouses are not legally required to have separate lawyers, but it is strongly recommended. One lawyer cannot represent both parties in a separation negotiation because there is an inherent conflict of interest — what is good for one client is often not good for the other.

Having independent legal advice (ILA) for both parties serves as strong evidence that each person understood the agreement and signed it voluntarily. Courts are more likely to uphold an agreement when there is a record that each spouse received independent legal advice. Many agreements include a clause confirming that each party received ILA and understood the effect of what they were signing.

If only one spouse has a lawyer and the other does not, there is an asymmetry of information and negotiating power that courts sometimes find problematic. A spouse who later claims they did not understand the agreement has a stronger argument if they can show the other side's lawyer drafted it and they had no one explaining their rights.

If cost is a concern, limited-scope retainers are available from many Ontario family lawyers. This means you pay for a lawyer to review the agreement and provide a letter of ILA, without hiring them for full representation — which significantly reduces the cost while still providing the protection.