One thing couples in Ontario getting ready to "tie the knot" may not know is that pursuant to Section 15(a) of Ontario's Succession Law Reform Act (SLRA) marriage will revoke a previously made Will. There are a few limited exceptions to this rule, but generally speaking, a Will made before marriage is invalid. The effect of a revoked Will is that on the testator's death his assets will be distributed pursuant to the SLRA's rules of intestacy.
Couples soon to be married could take advantage of one of the exceptions set forth in Section 16 of the SLRA which provides that a Will is not revoked when there is a declaration stating that it was made in "contemplation of the marriage."
Unless newly married couples made Wills "in contemplation of their marriage" they should take steps to have new Wills prepared.