What is the difference between a Mutual and Mirror Will?

While you may have heard people refer to making a ‘Joint Will’ with their partner or spouse, these documents do not in fact exist in law and the terminology usually in reality refers to ‘Mirror Wills’ or to ‘Mutual Wills’. Although these are types of wills there is a significant difference between them.

What is a Mirror Will?

A mirror will is a will that is identical or very similar to the will of another person, usually a spouse or partner. It's a common approach for couples to ensure their assets are distributed according to their wishes after both partners have passed away.  

Key features of mirror wills:

• Identical or similar - both wills have the same basic structure and provisions.  

• Survivor benefits - typically, the surviving partner inherits the first partner's estate.  

• Final beneficiaries - after the death of the surviving partner, the assets are usually distributed to children, other family members, or charities.  

Mirror Wills can cause a problem if the surviving partner decides to change their Will after the death of the first partner or spouse and to leave their assets to someone different from what the couple had initially agreed. To avoid this couples sometimes make Mutual Wills instead. Mutual Wills (unlike Mirror Wills) cannot be changed so easily.

What is a Mutual Will?

A mutual will is a type of will where two people, typically spouses or civil partners, agree to leave their assets to each other upon the death of the first spouse, and then to a third party, such as their children, upon the death of the second spouse.  

Key characteristics of mutual wills:

• Contractual Agreement - there is a binding contract between the two individuals to keep the terms of the will unchanged.  

• Irrevocable - once the first person dies, the surviving partner cannot change the terms of their will.  

• Enforceable - if the surviving partner tries to change the will, the deceased's estate can take legal action to enforce the original terms.

The best way to conclusively show intent for mutual wills to be binding is to ensure that each will states it is a mutual will on its face. In the absence of that clear evidence, you can still prove a couple intended their wills to be mutual if you can provide other evidence such as :-

• supporting documents; or

• from independent witnesses who are prepared to say the couple intend the Wills to be mutual or

• from the couple’s conduct.

Example scenario for a mutual will

For example, a divorced woman has two adult children from an earlier marriage. Part of her divorce settlement included a house free of mortgage and she wants her children to inherit that house. She decides to re-marry and her new husband has no assets, but he has an adult child. The couple make Mutual Wills whereby they agree to leave each other what they own but on the death of the second spouse the children of the woman will inherit the house.

With Mutual Wills, if the woman dies first, her surviving husband will take possession of the house for his lifetime but on his death, he must leave it to the woman’s children.

If the Mutual Wills state they are mutual Wills the couple will both be bound by the agreement. That means the surviving spouse cannot break the agreement by leaving the house to anyone but the children of the woman. If in fact the surviving husband decides to break the agreement and leave the house to his child, the children of the woman will have the right to enforce the agreement under the Mutual Wills.

Disputes over mutual wills

While relatively few Mutual Wills are made each year, they are the subject of a disproportionately large number of legal cases.

It therefore makes sense to take legal advice when making your will.