A joint will (a single will for a married couple) might sound like a great idea—after all, if you and your spouse have the same wishes for what you want to happen to your property after your death, why not sign a single document and be done?
These days, joint wills are seen as problematic, and estate planning lawyers rarely recommend them. Below is an overview of why.
A joint will is a single will signed by two people, usually a married couple, that sets out how to distribute the couple's property after they have both died. Commonly, a joint will contains language that makes it irrevocable after the death of a spouse—meaning that once one of the spouses dies, the will can no longer be changed by the surviving spouse. This is the characteristic that makes joint wills so problematic.
Mirror wills (also called reciprocal wills), unlike joint wills, are separate documents. With mirror wills, each spouse in the couple makes an individual will, but the wills contain reciprocal or "mirror" language. (In other words, Spouse 1 gives property to Spouse 2, while Spouse 2 gives the same property to Spouse 1. If they are a married couple with children, often both wills also state that their children will receive the remaining property after both spouses are dead.)
Mirror wills can sometimes also contain an agreement between the spouses that neither spouse will revoke their individual will. (And in the past, courts have sometimes inferred such an agreement even when the wills lack this explicit language.) If a mirror will is irrevocable in this way, it will also suffer from many of the problems discussed below.
As a starting matter, joint wills simply aren't legal in some states. In those states, if you make a joint will, the court will try to separate it into two wills.
The main issue with joint wills is that they tie up the hands of the surviving spouse. This is also what makes it attractive to some. For example, if you're worried that after you die, your spouse might remarry and then give away your property, you might be considering an irrevocable joint will.
But a joint will is not a nuanced solution to this problem. It might prove to be so inflexible that the surviving spouse faces unanticipated results. For example:
Example: Lina and Adam make a joint will that leaves their assets to their children. Unfortunately, after Adam dies, their son Oscar develops proves to be ill-suited to managing his own money, and racks up tens of thousands in credit card debt. Lina would like to make a spendthrift trust for Oscar, rather than giving him the money outright upon her death, but she can't change the joint will.
Example: Lina and Adam make a joint will leaving their home to Adam's children from a previous marriage. When she turns seventy, Lina decides she would like to move into a smaller home, but she might be unable to sell her current home to pay for it because Adam's children might have a claim to the home.
In addition, the probate process for joint wills can also be more complicated, which can result in expense and delays. In general, joint wills simply create more confusion and family disputes, which can cost time, money, and heartache.
So what's the best type of will for married couples, if not a joint will? Couples should make separate, individual wills that are revocable, so that they remain flexible as circumstances change. If your situation is uncomplicated, you can make separate wills for a married couple even without a lawyer's help, for example by using a reputable service such as WillMaker.
But if you have specific concerns—such as wanting to place restrictions on what your spouse can do with your property after you die—you should see an estate planning attorney. Many different types of trusts can address situations like this, and with more precision than joint wills.