Thanks for your question. I will try to help.
Unfortunately, what you have done is a breach of your residential mortgage conditions. It is a condition of your mortgage that you must advise them when you move out and a further breach to let the property without the lender’s consent.
It is technically a form of mortgage fraud, albeit not as serious as other forms of mortgage fraud.
Basically, it would be up for the lender to decide what to do once they found out. They may decide to issue you with a consent to let and charge you their fees for this with possibly an increased premium to your interest rate. In the long run, they will also require you to either repay the mortgage (ie by remortgaging with someone else) or by switching to a buy-to-let mortgage (at a higher interest rate) with someone else.
You are basically going to have to (1) allow the fraud to continue (risky if they find out because they are likely to take a less sympathetic view than if you disclosed), (2) remortgage to a buy to let with another lender and repay their charge, (3) disclose the letting to your current lender and see what they propose to do or (4) sell the property.
It’s also important to note that it could affect your future ability to get a mortgage if a breach of a mortgage condition is noted against your file.
I am could not have better news for you.
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