State laws differ. Many states regard property left to an ex-spouse as if he or she died before you, so it falls into your residuary, what remains after all other beneficiaries get their gifts. Alternatively, the court has your property pass to your heirs under intestate succession, as if there was no Will.

Under some state laws, if you get divorced after you’ve written a Will, the spouse is automatically eliminated as a beneficiary when the divorce is final, though he or she may still inherit other assets by operation of law or statute. Under other state laws, the Will is automatically revoked and you need to write a new Will, or risk dying intestate.

Since state laws vary, the disposition of property can be further complicated when a divorce occurs in one state, but the laws of another state govern the estate plan or beneficiary designation.

Given the complexity of the laws, you should change your Will upon divorce, or even upon legal separation. If the law regards your spouse as having predeceased you, you probably want to control who gets your property. More importantly, your ex-spouse may decide to contest the Will, delaying the probate process and costing your estate a lot of money to defend.

And you should consult an estate attorney, especially if you live in Pennsylvania, where you are considered legally married until the judge signs the final divorce decree and there is no such thing as legal separation. This means that if you die before the divorce is final, your soon-to-be ex is still considered your spouse for the purposes of your estate and is entitled to claim the spousal share of 1/3 of the assets. If you willed your entire estate to your spouse, and failed to change the Will, your spouse gets everything. If you do change your Will before the divorce is final, you can hope that your almost ex-spouse gets only the spousal share. The original Will is valid even if the divorce proceedings have been going on for 3 years and you’ve been separated for 10!