Mortgage and moving in with partner?

Me and my boyfriend both have our own properties and live apart. we both have mortgages. what would happen to my mortgage if i was to sell my house and move in with him? do i add my mortgage to his and start paying towards his mortgage? does my outstanding loan amount get added onto his outstanding mortgage amount and then a new repayment amount is calculated?
Answer
You sell your house and repay the money you owe with that, you get to keep any profit. make sure u get ur name added to your bf mortgage!