Will execution

An overview of the practical formalities required to make a valid Will, referred to as ‘due execution’.


In order for a Will to be valid, it must be duly executed in accordance with s9 of the Wills Act 1837.  If these strict requirements are not met, the Will is not valid.

This briefing note will give an overview of the practical formalities required to make a valid Will, referred to as ‘due execution’. 

Age, capacity, undue influence, knowledge and approval

The general rule is that at the time of making a Will, the person making it (known as the ‘testator’) must have reached the age of 18 and be of sound mind.  They must also be free from undue influence and know and approve of the contents of the Will.  We have separate guidance notes on each of these topics if required.

A Will must be signed and witnessed

A Will must be made in writing and signed by the testator in the presence of two witnesses.  Both witnesses must be present at the same time and the testator must sign the Will in front of them.  They must both then sign the Will to confirm that they witnessed the testator’s signature.

An additional point is that the testator must be actually intending to make a Will by his signature.  If he believes the document is something other than a Will, it will not have been validly executed.

There are circumstances where the testator need not sign a full signature, or even ‘sign’ his name at all, and in those cases anything intended as a signature will have that effect.  For example this may be relevant where a testator is unable to sign their name due to being too frail.

It is also permitted, in certain circumstances, that someone else may sign the Will on behalf of the testator, though this must be in his presence and at his direction.

Who can be a witness?

The only class of people who are excluded from being witnesses are blind people.  However, the suitability of a witness should be considered as they may need to give credible evidence about the execution in the future.  For this reason, minors and people who lack mental capacity should not be used as witnesses, although the Will cannot be declared invalid for this reason unless it can be proved that it was not witnessed correctly.

In addition, there is a rule that a witness cannot benefit from a Will.  If a beneficiary does witness the Will, it does not make the Will invalid in its entirety, but this means that any gift to that beneficiary or their spouse will fail.  

Presumption of due execution

If a Will appears to have been correctly executed on its face, there is a presumption that the necessary formalities have been complied with.

This presumption is rebuttable, although anyone seeking to challenge a Will needs evidence to support their claim.  Examples of such evidence may include proving it is not the testator’s signature (perhaps using a handwriting specialist), or evidence that both of the witnesses were not present at the same time.

If there is any doubt about whether the Will was correctly executed, the witnesses (if still alive and traceable) should be asked to complete an affidavit confirming their recollection of events and whether it was executed in line with the required formalities.


As outlined above, the requirements for due execution of a Will under the Wills Act 1837 are strict and if those provisions are not complied with, the Will is invalid.

If you believe any of these issues may be relevant to a matter which you are involved in, please contact us for further advice.

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Every piece of content we create is correct on the date it’s published but please don’t rely on it as legal advice. If you’d like to speak to us about your own legal requirements, please contact one of our expert lawyers.

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