What is a mirror will?
A mirror will is one of a pair of almost identical wills, usually made by a couple, that "mirror" each other. Each leaves their estate to the other partner first, and then to the same chosen beneficiaries — typically their children — when the second partner dies. They are two separate wills, not one joint document, and either person can change their own will at any time.
Detailed explanation
Mirror wills are the most common arrangement for couples — married, in a civil partnership, or cohabiting — who share the same wishes. Each partner makes their own will, and the two are drafted as near-identical reflections of each other:
- Partner A leaves everything to Partner B; if B has already died, to the children (or other chosen beneficiaries).
- Partner B leaves everything to Partner A; if A has already died, to the same beneficiaries.
They are efficient and inexpensive because the drafting is shared, and they give couples reassurance that the survivor is provided for and the estate ultimately reaches the people they both care about.
The key limitation is that mirror wills are not binding. Each is an independent will. After one partner dies, the survivor is completely free to make a new will — even one that disinherits the original beneficiaries, for example after remarrying. This surprises many couples, who assume the arrangement is locked in.
Couples who genuinely need certainty that the survivor cannot change course sometimes look at mutual wills (a binding agreement not to change) or a life-interest trust (letting the survivor benefit during their lifetime while protecting the underlying capital for children). Both are more complex, can cause disputes, and should only be set up with specialist advice. For most couples, mirror wills remain the practical default.
Tom and Aisha make mirror wills: each leaves everything to the other, then to their two children. Tom dies, and Aisha inherits everything. Years later Aisha remarries and makes a new will leaving her estate to her new husband. Because mirror wills are not binding, this is entirely lawful — and the original children could be left out. A trust-based arrangement would have protected their share.
Sources
- Wills Act 1837 — legislation.gov.uk
- GOV.UK — Make a will
- STEP — guidance on wills and will trusts
- Reviewed by
- Michael Smith, Estate Planning Specialist
- Last reviewed
- June 2026
- Next review
- December 2026
- Jurisdiction
- England & Wales
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