Mirror Wills – Simple, Popular, and Sometimes Very Dangerous

Colin Barrett
Apr 2
3 min read

Mirror Wills are one of the most common types of Wills used by married couples. They are simple, easy to understand, and in many situations they work perfectly well.

But in some circumstances, mirror Wills can lead to very serious unintended consequences, including children being disinherited entirely.

That is why it is important to understand not just how mirror Wills work, but also where the risks lay.

What are mirror Wills?

Mirror Wills are usually made by couples and are almost identical to each other. Typically they say something like:

Everything passes to the surviving spouse
When the second person dies, everything passes to the children

On the face of it, this seems perfectly sensible. Most couples want the survivor to inherit everything, and then the children to inherit when the second person dies.

The problem is not what happens when the first person dies. The problem is what can happen afterwards.

What happens after the first death?

When the first person dies and everything passes to the surviving spouse, those assets now belong entirely to the survivor. They can spend the money, give it away, change their Will, remarry, or leave everything to someone else.

The mirror Will does not lock anything in place after the first death.

This means that the final destination of the estate is entirely dependent on what the surviving spouse does later in life.

How children can accidentally be disinherited

This is sometimes called “sideways disinheritance”, and it happens more often than people realise.

For example:

The surviving spouse remarries and leaves everything to the new spouse
The surviving spouse changes their Will after a disagreement with one child
The surviving spouse gives money away during their lifetime
The surviving spouse is influenced by someone else
The surviving spouse becomes bankrupt or has financial problems

In all of these situations, the children from the original marriage may receive far less than intended, or sometimes nothing at all.

This is usually not what the first person to die would have wanted, but because everything passed outright to the survivor, there is nothing to stop it happening.

When mirror Wills are perfectly fine

Mirror Wills are not always a bad idea. In many situations they are perfectly reasonable, for example:

Second marriages where both spouses intend to leave everything to each other and then to shared children
Smaller estates where trust planning would be disproportionate
Couples who are very comfortable with everything passing outright to the survivor
Situations where asset protection is not a concern

The key point is that mirror Wills are not wrong, but people should understand the risks before deciding to use them.

An alternative approach

In many cases, couples instead use a Will trust so that when the first person dies, their share of the estate is held in trust rather than passing outright to the survivor.

The survivor can still live in the house, still receive income, and still be financially secure, but the underlying capital is protected so that it ultimately passes to the intended beneficiaries, usually the children.

This can protect against:

Remarriage
Bankruptcy
Changes of Will
Sideways disinheritance

It is not the right solution for everyone, but it is something many couples should at least consider.

The important thing is understanding the choice

The biggest issue I see is not people choosing mirror Wills. The biggest issue is people choosing mirror Wills without understanding the consequences.

Estate planning is not just about what happens when the first person dies. It is about what happens after both of you are gone.

And sometimes the simplest plan is not always the safest one.