One will, two countries, and an executor who finds out too late

Figures relate to tax year 2025-26 (UK) · 2025 (US)

An American signs a will in London. It is valid, properly witnessed and does exactly what it says.

The difficulty is what it did to the American one. A standard UK will opens by revoking every earlier will, wherever it was made.

So a document drafted to cover a flat in Clapham can quietly cancel the arrangements for a house in Ohio. However, the executor rarely finds out until probate.

Key takeaways

• A UK will usually revokes every earlier will unless it says otherwise.
• A second will can coexist with a UK will when each covers its own country.
• Mirror wills between spouses are convenient rather than binding.
• Your executor needs authority recognised in both countries.
• A lasting power of attorney has no American equivalent that travels.
• Marriage revokes a UK will automatically unless it anticipates the wedding.
• Dying without one hands the division to statute, not to your family.
• Review the documents whenever you move, marry or buy property.

What does a UK will actually do?

It appoints people and divides things. You name executors who gather the estate, and you say who receives what. According to GOV.UK guidance on making a will, it needs two witnesses who are not beneficiaries. Signing it correctly matters more than the wording people worry about.

It takes effect only on death and can be replaced at any time.

Nothing in it binds you while you are alive.

Does an American need a separate US will?

Often yes, where real property sits in America. Land passes under the law of the place it stands, so a house in Texas is governed by Texan rules whatever a London document says. A second will, limited to American assets, keeps that straightforward.

Investments and bank accounts are usually more flexible.

Property is the part that forces the issue.

What are mirror wills?

Two near-identical wills, one for each spouse. Each leaves everything to the other, then to the children. They are popular because they are simple, and they are misunderstood because they bind nobody. The survivor can rewrite theirs the following week.

That freedom matters most in second marriages.

A trust is the usual answer where it does.

Can one will cover both countries?

It can, and for simple estates it often should. A single worldwide will avoids the revocation trap entirely and leaves one executor in charge. The cost is a slower probate in the second country, because the document has to be proved abroad first.

Two wills run in parallel and finish sooner.

One will is tidier but slower to administer.

Who should be your executor?

Somebody who can act in both places, or one person in each. A British executor with no American standing cannot close a US brokerage account, and an American executor may struggle with HMRC. Naming a professional alongside a family member often solves it.

Our guide to an American executor's UK duties covers the role.

Ask them before you name them.

What happens without a will?

Statute divides the estate, and it rarely matches anybody's intention. In England the rules give a spouse a fixed sum and a share, with the rest to children. An unmarried partner receives nothing at all, however long you lived together.

American intestacy rules differ again, state by state.

Two sets of default rules is the worst outcome.

Does a new will revoke the old one?

Almost always, because the standard opening clause says so. A properly drafted cross-border document limits that revocation to wills covering the same assets. One clause is therefore the difference between two documents working together and one destroying the other.

Check this clause on anything already signed.

It is the single most common defect we find.

Where should the UK will be stored?

Somewhere your executor can actually reach it. A signed original is what probate needs, and a scan will not do. Tell at least two people where it sits, because an estate can stall for months while a family searches a house.

Solicitors and the probate service both store originals.

Keep both countries' documents together.

Do you need witnesses in both countries?

No, one proper signing is enough for each document. English law wants two witnesses present together, while American states vary and some allow a self-proving affidavit. Follow the rules of the place the will is made and it will generally be respected elsewhere.

Witnesses must not inherit anything under it.

A beneficiary witness loses their gift.

What about a lasting power of attorney?

This is the gap almost nobody closes. A lasting power of attorney covers decisions while you are alive and incapable, and it is a British creature with no travelling equivalent. An American durable power will often be refused by a UK bank.

Most people need a document in each country.

Register it before you need it, not after.

Does marriage revoke a UK will?

In England it does, automatically, unless the will was made in contemplation of that marriage. So a couple who marry after signing may be intestate without realising. Divorce does not revoke the whole document, but it treats the former spouse as having died first.

Review the papers around any change in status.

American states handle this differently again.

What does probate involve here?

An application for authority, then the work of collecting and distributing. The executor values the estate, settles what is due and applies for a grant. Per GOV.UK guidance on probate, that grant is what banks and registrars will want to see.

A straightforward estate takes several months.

A cross-border one usually takes a year or more.

A worked example

Take an illustrative example. An American who has lived in London for twenty years signs a British will covering her flat and her savings here.

She already had an American will dealing with a family house in Oregon and a brokerage account.

The new document opens with a general revocation clause, so the earlier one falls away.

Her executor finds the Oregon house passing under intestacy rules nobody chose, to people she had not intended.

One estate, two systems

How does domicile come into it?

It decides how much of your estate Britain can reach. Somebody treated as domiciled here faces inheritance tax on worldwide assets, while others face it only on British ones. Long residence now drives that status rather than the older common law test alone.

Our guide to long-term residence and inheritance tax covers the current rule.

Domicile is slow to change and easy to assume wrongly.

Does the IRS care what the will says?

Only for what it produces. America taxes the estate of a citizen wherever they lived and whatever document divides it. The will shapes who receives what, and that in turn shapes which reliefs apply, so the drafting has tax consequences even though it claims none.

Our guide to UK inheritance tax meeting the US system covers the overlap.

Citizenship follows you regardless of where you sign.

What about the spouse exemption?

It is generous on both sides, with one large exception. Britain allows an unlimited transfer between spouses, and America does the same where the surviving spouse is a citizen. Leave everything to a British husband or wife and the American exemption shrinks dramatically.

Our guide to the marital deduction for a non-citizen spouse covers the fix.

A qualified trust is the usual workaround.

Does a non-citizen spouse change the drafting?

Considerably, and this is where a standard high street will struggles. The document may need to create a particular kind of trust to preserve the American relief. That is a drafting decision, so it has to be made before signing rather than afterwards.

Our guide to UK trust distributions and US reporting covers the aftermath.

Retrofitting this after a death is rarely possible.

What about US retirement accounts?

They pass outside the will altogether. An individual retirement account or a workplace plan goes to whoever is named on the beneficiary form, and that form beats any will. So an out of date nomination can override a carefully drafted document completely.

Our guide to US retirement accounts in the UK covers the tax.

Check every nomination when you review the will.

What about a UK pension death benefit?

Also outside the will, and usually at the trustees' discretion. You complete an expression of wish, which guides them without binding them. That discretion is deliberate, because it keeps the fund outside the estate for British purposes.

Our guide to UK pensions and US tax covers the treaty position.

Update the expression of wish after any family change.

Does a trust in the will cause problems?

It can, because a trust created by a British will is foreign to the IRS. Beneficiaries may pick up annual reporting they never asked for, and the trust itself may face American charges. None of that makes a trust wrong, but it makes it a decision.

Our trusts and estates service covers the reporting.

Model the American side before drafting it in.

What about property in both countries?

Real estate is the strongest argument for two wills. A house passes under local law, and a foreign grant of probate can take many months to be recognised. Keeping each property under a document made where it stands shortens the whole process.

Our guide to second homes across the two systems covers the lifetime tax.

Joint ownership changes the answer again.

Does it affect your children?

It does, especially where they hold American citizenship. A child who inherits a British trust interest acquires American reporting with it. Equally, a child born here to an American parent may be a US person without ever having lived there.

Guardianship clauses matter as much as money.

Name guardians who can act in the country they live in.

What if you renounce?

Renunciation removes the citizenship link but not necessarily the estate exposure. A covered expatriate can leave a charge behind for American beneficiaries who inherit later. So the will and the exit should be planned in the same conversation.

Our guide to renouncing US citizenship covers the exit.

The documents usually need rewriting afterwards.

Do you need a solicitor in both countries?

For anything beyond a simple estate, yes. Each lawyer drafts for their own jurisdiction, and the value comes from making the two documents agree. Ask each one to read the other's draft before anybody signs anything.

That single step prevents most revocation accidents.

Budget for the review rather than skipping it.

How often should you review it?

Every five years, and immediately after any major change. A move, a marriage, a birth, a property purchase or a change in residence status all shift the answer. A will written for a different life is worse than no plan, because it looks finished.

Diarise the review with your tax return.

Most defects we see are simply out of date.

What should your executor have?

A list, kept with the will and kept current. It should name every account, property, pension and adviser in both countries, with contact details. Without it an executor spends the first six months discovering what exists before doing anything useful.

Include your American filing history and adviser.

That list saves more time than any clause.

Does life insurance sit outside it?

Usually, provided the policy is written in trust. A policy held that way pays the beneficiary directly and stays outside the estate for British purposes. The same policy may still count for American estate tax, which catches people out.

Our guide to death in service benefits covers the employer version.

Ask whether the policy is actually in trust.

What about digital assets?

They need naming or they vanish. Cryptocurrency, domain names and online businesses are often invisible to an executor and inaccessible without keys. A list of what exists, stored separately from the passwords, is the practical answer.

Never put passwords in the will itself.

A will becomes a public document after probate.

How much is actually at stake?

More than people expect. Britain charges inheritance tax at 40% above a nil-rate band of £325,000 in 2025-26, with extra relief for a family home. America sets its own exclusion far higher, so the British charge is the one that usually bites first.

A UK will cannot change those figures.

What it changes is who pays them.

Does a UK will help with the tax at all?

Only through who inherits. The document cannot cut a rate or lift a band. What it does decide is which exemptions apply. Gifts to a spouse, a charity or a trust produce very different bills from the same estate.

A large enough charitable gift cuts the British rate to 36%.

So the drafting is worth money, not just tidiness.

How to plan a cross-border will

1. List every asset in both countries, with how each is owned.
2. Decide whether a single worldwide will or a separate UK will suits you.
3. Check the revocation clause on any UK will already signed.
4. Choose executors who can act in each country involved.
5. Model the position where your spouse is not a US citizen.
6. Put a lasting power of attorney in place on the British side.
7. Update beneficiary nominations and expressions of wish.
8. Have each country's adviser read the other's draft before signing.

Mistakes and penalties we see with cross-border wills

The first is a general revocation clause that quietly cancels the other country's will.

The second is leaving everything to a non-citizen spouse without considering the American relief.

The third is forgetting that retirement nominations beat the will entirely.

The fourth is creating a trust in the will without pricing the American reporting it brings.

How US UK Tax Accountants helps

We work alongside the solicitors rather than replacing them, because the drafting is theirs and the tax consequences are ours. The value sits in making the two documents agree before anybody signs.

We also model what each version costs the estate. Our trusts and estates work covers the American exposure.

If you signed a British will after arriving here, get in touch and let us check the revocation clause.

Last reviewed 20 October 2026. This article is general information and not personal tax advice, and nothing here is a substitute for legal drafting advice.