What can I do if my partner refuses to sign a cohabitation agreement in Ontario?

Ontario law does not require a common-law partner to sign a cohabitation agreement, and there is no legal mechanism to compel them to do so. If your partner refuses, you cannot force the issue.

That said, there are practical steps you can take to protect yourself without a formal agreement. You can keep your own financial records documenting contributions you make to jointly used property, which would support a trust claim later if needed. If you intend to purchase property together, you can ensure it is titled correctly (in both names with explicit ownership proportions recorded on the deed) rather than leaving it solely in your partner's name.

You can also maintain separate bank accounts and keep paper trails showing which funds belong to whom. For large assets like a home or investment portfolio, speaking with a lawyer about how to structure the ownership before purchase is more effective than trying to unwind it after the fact. If the relationship has children or involves significant shared assets, the risks of having no agreement are real, and it may be worth having an open conversation with your partner about what each of you is worried about — sometimes resistance comes from not understanding what the agreement is intended to do.