A neighbour or friend may seem an obvious person to witness your will. Before asking, however, check whether they or their spouse or civil partner receive anything under it. The witness's relationship to the gifts matters just as much as their availability.
Under Irish succession law, a gift to an attesting witness, or to that witness's spouse or civil partner, is generally void. This does not necessarily invalidate the whole will, which can make the mistake particularly easy to miss: the document may survive while the intended gift does not.
Choose independence and reliability
The safest practical choice is two independent adults who are able to observe the signing and could give a clear account of it if required. Avoid beneficiaries and their spouses or civil partners. Where possible, also avoid involving someone whose participation might create an unnecessary dispute about influence.
A witness is confirming the signing process, not approving the fairness of your decisions. They need not be given a detailed explanation of the estate or shown every gift. They should nevertheless understand that they are witnessing your signature on a will.
Must the witnesses be together?
You must sign or acknowledge your signature with both witnesses present at the same time. Each witness then signs in your presence. Arranging for everyone to remain physically together until the document is complete is a straightforward way to avoid errors.
Asking one person to sign on Monday and another on Tuesday does not reproduce that process. Nor should a witness simply sign a document that someone else brings to them when you are absent.
What about an executor?
The Succession Act allows an executor to act as a witness. But if that executor is also a beneficiary, the gift problem still arises. There is rarely a good reason to introduce that complication when independent witnesses are available.
Check the witness details before putting the will away. Legible names and contact information can make later enquiries easier, especially if many years pass before the will is used.
If your circumstances require unusual signing arrangements, speak to a solicitor. It is better to organise a suitable meeting now than leave your executor to resolve doubts when you are no longer able to explain what happened.
Sources and further reading
General information, not advice on your individual circumstances. Laws and tax rules can change; check the linked official guidance and obtain professional advice where needed.