Changing a will: codicils, new wills and what marriage does

When a will needs looking at again

A will is a snapshot of a family and its assets on the day it was signed. The events that most often make one out of date are predictable, and each one is a reason to read the will again.

Marriage, remarriage, separation, divorce, the birth of a child or grandchild, a death in the family, moving house, receiving an inheritance, buying or selling a business, and taking on or paying off substantial debt. So is a change in who you would trust to act, since executors and guardians appointed fifteen years ago may no longer be the right people or may no longer be alive.

Two changes that people overlook are worth naming. The first is a pension or life policy nomination, which usually passes outside the will entirely and therefore has to be reviewed alongside it. The second is a change in the law: the inheritance tax treatment of unused pension funds changes for deaths on or after 6 April 2027, and wills written on the old assumption are worth reading again in light of it.

What a codicil is and when it works

A codicil is a separate document that amends an existing will while leaving the rest of it standing. It has to be signed and witnessed with exactly the same formalities as a will: two witnesses, both present at the same time, each signing in the presence of the person making it.

Because the formalities are identical, a codicil saves no effort beyond the drafting. It suits a genuinely small change: replacing an executor who has died, adding a modest legacy, correcting a misspelled name or address.

The risks come with volume. A will with three codicils has to be read as four documents together, and the scope for contradiction grows with each one. A codicil can also be separated from the will, so the two have to be stored together and cross-referenced. Where a change affects who receives the residue, or where more than one adjustment is needed, a fresh will is safer.

When a new will is the better answer

A replacement will revokes everything before it, provided it contains a revocation clause, and produces one single document that says what should happen. That clarity is worth a great deal when an estate is being administered by somebody who was not involved in the drafting.

A new will is the right choice where the residuary gifts change, where the family structure has changed, where a trust is being added or removed, or where the existing will has already been amended once. Given that the signing formalities are the same either way, the extra cost is usually the drafting alone.

Marriage revokes a will

Under section 18 of the Wills Act 1837, marriage or the formation of a civil partnership revokes any existing will automatically. The person marrying does not have to know about the rule, and nothing has to be done for it to take effect.

The consequence is that somebody who made a careful will and then remarried may die intestate without ever realising it, with the estate passing under the statutory rules to the new spouse and any children in fixed shares. In a second marriage, where the intention was usually to provide for children of the first, this can produce the opposite of what was wanted.

There is one exception. A will made in express contemplation of a particular marriage, which states that it is not to be revoked by that marriage, survives it. The wording has to be specific about the intended marriage, so a general reference to a future marriage does not help.

Divorce does something different

Divorce does not revoke a will. The will continues in force, and the former spouse is treated as having died on the date the marriage ended.

That produces two effects that are easy to miss. Any gift to the former spouse fails, and any appointment of them as executor fails. If they were the sole residuary beneficiary and no substitute was named, the residue passes under the intestacy rules, which may take it to relatives the person had no wish to benefit.

The rule applies from decree absolute or final order, so a will made during a separation continues to benefit the spouse in full until the divorce is finalised. Anybody who has separated but not divorced and wants to change who benefits has to make a new will to do it.

Why crossing things out does not work

Alterations made to a will after it has been signed are presumed to have been made afterwards and are generally ineffective, unless they are signed and witnessed in the margin with the same formalities.

So crossing out a beneficiary's name, writing in a different figure, or adding a line in the margin usually changes nothing. The original wording stands if it can still be read. Where an obliteration makes the original impossible to read, the position becomes complicated and may require an application to the court.

Alterations also raise questions about the whole document: when were they made, by whom, and did anybody else have access to the will. A marked-up will invites exactly the kind of investigation that leads to a caveat.

Revoking a will deliberately

Section 20 of the Wills Act 1837 allows a will to be revoked in three ways: by a later will or codicil, by a signed and witnessed written declaration of revocation, or by burning, tearing or otherwise destroying it with the intention of revoking it.

Destruction has to be both physical and intentional. A will torn up by somebody else, or destroyed by accident, is not revoked, and a copy can be admitted to probate with evidence of the contents.

Revoking a will without making a new one leaves the intestacy rules in charge, which is rarely what anybody intends. The safer sequence is to sign the new will first and destroy the old one afterwards.

Promises, mutual wills and property abroad

Freedom to change a will has three limits worth knowing about.

The first is mutual wills. Where two people make wills on identical terms and agree that neither will change theirs after the first death, the survivor can be held to that agreement in equity even though the later will is valid. The agreement has to be proved, and the courts require clear evidence of a binding promise, so wills that merely mirror each other are not enough. Couples in second marriages sometimes want this effect and it is safer achieved through a trust, which does the same job without locking somebody into a document for the rest of their life.

The second is proprietary estoppel. Somebody who was promised property, relied on that promise to their detriment and would suffer injustice if it were broken can enforce it against the estate. The farming cases are the well-known examples: decades of low-paid work on a promise of inheriting the land. A will that breaks such a promise can be overridden.

The third is foreign property. Land abroad is generally governed by the law of the country it sits in, and some countries apply forced heirship rules reserving fixed shares for children whatever the will says. A separate local will may be needed, and where one is made it has to be drafted so that the two wills do not revoke each other. This is where a revocation clause in an English will causes real damage if it is written without knowing a foreign will exists.

Where the will should be kept

Probate is granted on the original will, so the original has to be produced. Where the original cannot be found and it was last known to be with the person who made it, the law presumes they destroyed it with the intention of revoking it, and that presumption has to be rebutted with evidence.

That makes storage a practical matter. A will kept with the firm that drafted it, or deposited with the Probate Service, is traceable. A will kept at home can be lost in a house clearance, damaged, or thrown away by somebody who does not recognise what it is. Wherever it is kept, the executors need to know where to look.

Three habits cause avoidable trouble. Stapling or pinning anything to a will leaves marks that suggest a document was once attached and later removed, and the Probate Service asks about them. Keeping the will loose in a folder with older drafts makes it harder for an executor to identify which document is the operative one. And storing the only copy in a bank safe deposit box can be awkward, because the bank may want to see a grant of probate before releasing the box, while the grant requires the will inside it.

Alongside the will itself, executors benefit from a short note of where things are: which bank holds which account, where the deeds and pension paperwork sit, who the accountant is, and whether any funeral wishes have been expressed. A note of that kind carries no legal force and changes nothing about the will, and it saves weeks of searching at the point when the family has least energy for it.

Frequently asked questions

Do I need a new will if I get married?

Yes, in almost every case. Marriage or forming a civil partnership automatically revokes any will you already have, under section 18 of the Wills Act 1837, so you would die intestate and the statutory rules would decide who inherits. The exception is a will made in express contemplation of that particular marriage, stating that the marriage is not to revoke it. If you married after making your will and did nothing since, you have no will.

Does divorce cancel my will?

No. The will stays in force and your former spouse is treated as having died on the date the marriage legally ended. Any gift to them fails and their appointment as executor fails. The problem is what happens next: if they were your only residuary beneficiary and you named no substitute, the residue passes under the intestacy rules. The rule only applies from the final order, so a will made during a separation still benefits your spouse in full.

Can I just cross something out on my will?

No. An alteration made after the will was signed is presumed to have been made after execution and is ineffective unless it is signed and witnessed in the margin with the same formalities as the will itself. The original wording stands if it can still be read. Marking a will also raises questions about when and by whom, which is the kind of doubt that leads to a dispute. Use a codicil or a new will.

How much does it cost to change a will?

It depends on whether a codicil or a replacement will is appropriate. Since the signing formalities are identical either way, the difference is in the drafting, and for anything beyond a very small change a new will usually costs little more and produces one clear document. Our fixed fees for wills and codicils are published on the AD Wills prices page, and you get the fee in writing before any work starts.

How often should I review my will?

Read it again whenever something changes in the family or the assets, and otherwise every five years. The events that matter most are marriage, separation and divorce, births and deaths, moving house, receiving an inheritance, and starting or selling a business. Review the things that pass outside the will at the same time, particularly pension nominations and life policies, because those frequently carry more value than the will itself.

What happens if the original will cannot be found?

If the will was last known to be in the possession of the person who made it and cannot be found after their death, the law presumes they destroyed it intending to revoke it. That presumption can be rebutted with evidence, and a copy can be admitted to probate where the court is satisfied about the contents and that it was not revoked. It is an expensive argument to have, which is why storage and telling the executors where to look both matter.

Sources & further reading

• Wills Act 1837
• GOV.UK: making a will
• GOV.UK: storing a will with the Probate Service
• Administration of Estates Act 1925, section 46

This article is general information, not legal advice. The law changes and depends on your circumstances — always take advice on your specific situation before acting. Last reviewed 21 September 2026. AD Solicitors Limited is a recognised body regulated by the SRA (no. 8011228).