Do I need deed poll to now go by double barrelled name

[Milly90]

Hi
tried to Google but unclear

married 10 years very happy marriage but I married young (21) and now wish I had retained some element of my own identity

so if I was miss jones and married mr smith, I am now Mrs smith but I have decided I want to be mrs smith-jones do I need to change this by deed poll or can I just now be known as this? If I wanted to change my passport and driving licence would this be deed poll? Or can I provide my marriage and birth cert at that stage and change it?

we have dc who are ‘child smith’ wouldn’t be looking to change this

any ideas? Thanks in advance

Legally, you don't have to change by deed poll to start using your new name. However I found that banks etc wanted to see a deed poll in order to change my name on their records - they wouldn't accept birth/marriage certificate. Definitely simpler just to get one.