Hi
As you have income from property, you meet the criteria for completing a self assesment tax return.
You can register for self assessment at
Check how to register for Self Assessment, if you have not done so.
The tax return is for you to declare all of your world-wide income and capital gains. This includes the interest from your bank.
The self assessment calculation will allow up to £1000 of interest tax free, if your are a basice rate taxpayer or £500 if you are a higher rate taxpayer.
Whether there is tax to pay on the interest will depend on what is declared on the tax return.
Thank you