You can change your address details online. Simply log in, click on 'Account' and update your details.
If you've recently moved house, we'd suggest waiting 6-8 weeks to change your address details so your information is updated and you're registered to vote on the Electoral Register. Not being registered to vote can have a negative impact on you credit score.
The good news is you don't have to worry about missing anything in the post. BetterBorrow emails all of your important documents straight to you, wherever you are.