Advice for a woman on being widowed
If you have been widowed and you want to revert to your maiden name (or whatever name you were using before marriage), you do not need a deed poll — your marriage certificate and your late husband's death certificate together are sufficient evidence of your name change.
If you want to revert to a surname which was not your maiden name, or you want to change one of your forenames, then you will need a deed poll.
If your change of name needed a deed poll when you got married, then you will need a deed poll again to revert your name back — your late husband's death certificate (and your original deed poll) will not be enough.
To change only your title, there is no need for a deed poll — see the section on how to change your title.
Note that all of this advice applies equally to men that have been made widowers, and to civil partners.