Does a codicil need witnesses?

Yes — exactly the same as a will. You must sign it in front of two witnesses present at the same time, who then each sign in your presence, all in wet ink. The witnesses can be different people from those who witnessed the will.

Can I have more than one codicil?

Legally, yes — but each new codicil has to be read alongside the will and every earlier codicil, which is precisely how contradictions and disputes creep in. Beyond one or two tiny changes, a fresh will is the better tool.

How much does a codicil cost?

Solicitors typically charge £50 to £150 or more for a codicil — often not far off the price of a new will. With SwiftWill, you simply make a fresh will instead: updates are free for life after the one-time £35.

Codicil or new will — which should I choose?

A codicil suits one small, uncontroversial tweak, like swapping an executor's address. Anything more — new beneficiaries, changed shares, a marriage, divorce or new child — calls for a new will, which revokes the old one and leaves a single clean document.

Can I write a codicil myself?

You can, and it is legally valid if executed with the same formalities as a will. But DIY codicils carry the same drafting risks as DIY wills, plus the extra risk of contradicting the original document — one reason fresh wills have largely replaced them.

What Is a Codicil? Amending a Will (2026)

What is a codicil?

Quick answer

A codicil is a formal legal amendment to an existing will — a separate document that changes, adds or revokes specific clauses. It must be signed and witnessed with exactly the same formalities as a will. Because codicils can be lost or contradict the original, a fresh will is usually the safer choice.

The definition

A codicil is a formal amendment to an existing will — a separate legal document that changes, adds or revokes specific clauses while leaving the rest of the will in force. It dates from an era when rewriting a will meant rewriting every page by hand, and it survives today mostly for tiny changes: swapping an executor, updating an address, adjusting a single cash gift.

The formalities are identical to a will

Here is the part people miss: a codicil is not a casual note. It must be executed with exactly the same ceremony as the will itself — signed by you in the presence of two witnesses who are together at the same time, then signed by each witness in your presence, all in wet ink. The witnesses do not need to be the same people who witnessed the will, but the same rules apply: no beneficiaries, and no beneficiaries' spouses or civil partners. See how to sign a will for the full ceremony.

Why codicils cause problems

They get lost. A codicil stored apart from its will may never be found — and an unnoticed codicil that surfaces years later can upend an estate.
They contradict. Each codicil must be read against the will and every earlier codicil; ambiguity between documents is a classic source of disputes.
They revive what you meant to bury. A codicil republishes the will as at its new date, which can accidentally reinstate clauses you thought were gone.

The modern alternative: just make a fresh will

A new will revokes the old one entirely, leaving a single clean document that says exactly what you want now. For anything beyond the most trivial tweak, it is the safer choice — our guide to changing your will explains why. It is also why SwiftWill includes free updates for life: whenever life changes, you can make a fresh will in about 15 minutes rather than layering amendments onto an ageing document.