In general, spouses that have entered into a separation agreement do not typically intend their spouse to thereafter benefit from their estate. However, unless a separation agreement is very carefully worded, the wills made by the parties to a separation agreement, even if those wills predate the separation agreement and appear on their face to be contrary to the intention of the separation agreement, will be found to prevail.
This is because the Court is reluctant to override the testamentary dispositions made within a will unless the language of a separation agreement are direct and cogent that such is the intention of the parties to the separation agreement.
Rather than being a testamentary disposition, a separation agreement is a contract whereby the parties contract out of their entitlements to receive statutory benefits and testamentary dispositions if the agreement uses wording to effect such a result.
In Goldfield v. Koslovsky  2 WWR 553, the Court found that the parties to a separation agreement had not contracted out of the benefits conferred upon them by each other’s wills which predated the separation agreement. Specifically, the Court reasoned that “the Wife had no right to claim to be named as beneficiary of her former husband’s estate, but she did not by the agreement waive her right to claim if her husband chose not to alter his Will so as to eliminate her as a beneficiary.”
More recently, in Re Roth Estate (2009), 51 ETR (3d) 290, 2009 CarswellOnt 6432, a separation agreement, which specified that spousal support payments from the husband to his wife were variable only in the event of the husband predeceasing the wife, was effective in limiting the wife’s claim against her deceased husband’s estate.
There is a presumption that the will has not been revoked by the terms of the separation agreement. Such a presumption is rebuttable only if there are direct and cogent words in the separation agreement that specifically contemplate the situation in which the parties fail to change wills which predate the separation agreement and leave their respective estates to the other.
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