Most of us will have a deal offered by our mortgage lender when we get the mortgage, as it is important for most of us to get the best rate we can. There are many different types of mortgages available, fixed rate, discounted, variable, tracker - so it is important to get the one that is right for you. If you are unsure, then using a mortgage broker can help.
You will automatically transfer to the standard variable rate if you do nothing, which is usually more expensive. So you should think about remortgaging.
There are fees associated with this, and they will vary from lender to lender, so be prepared for some extra costs. Some of the lenders will charge as much as £1,000 to secure a new mortgage, and you should include these costs in any calculations to check you are getting the right deal.
You will need to get your solicitor involved to do the legal legwork for you, unless you can get a deal where legal fees are included, and the mortgage lender has a solicitor that will help you with this for no extra charge. However, be aware that you will usually pay for this in a higher interest rate, so it is not exactly 'free'.
If you are changing your mortgage lender, then you need to get a redemption statement from your existing lender, and that figure is what you need to work to so that your existing mortgage is paid off in full. The title deeds will be obtained from your lender by your solicitor, and any necessary searches will be carried out.
You will need to sign the mortgage deed and agree a date for completion, when the existing mortgage will be paid off, and the new mortgage registered with the Land Registry.