Legally you can be known by any name you want as long as you do not try and con or deraud anyone. i.e. a girl marrying can take on her husbands surname and I know a few who do that without getting married just to appear respectable or for the kids sake. I know others who revert to their Maiden Name.
For legallity purposes inform authority figures such as employers, driving licence, tax people, mortgage people etc. Might have to explain to passport folks.
You usally have 2 good proofs of id. You have a national insurance number and a tax reference number.
I have already got a new passport and driving license. I have also informed council tax, bank etc.
I was just concerned if i contacted mortgage lender they would ask quedstions about where ex lived and i don''t have an answer for that.
I have continued to pay mortgage for past 5 years so no problem with that.
Most lenders couldn''t care less where the money comes from as long as its paid. It could come from your granny for all that really matters !! If you rent for example the landlord isn''t really interested where your money comes from as long as you the tenant pay what is due. Could come from earnings DHSS etc.
Mortgages are secured on property and I would imagine that you have some equity in it by now.
The real problem comes when you want to sell. Property value excess must be split accordingly but a solicitor would help you out. Try tracing him down. Not for contact but so that if the needs be you can point people in right direction.
Companies like first locate (1stlocate) can trace for about £30 especially if you have NI numbers, date of birth etc.
I would think your lender would just change your details and carry on as usual .