How is tax paid on savings accounts

Hi there, Can someone help me understand how I pay tax owed on my savings interest? I have some fixed rate bonds maturing over the next few years and, as interest is paid gross by my bank and i am unable to access the interest until maturity, how do i go about paying the tax? Do HMRC change my tax code? Do HMRC send me a bill to pay it? If tax is paid by changing my tax code, does what i owe get taken out of my wages each month, spread over the following tax year? And does the tax code only change at the start of the new 2025 tax year, even if my bond matures in July 2024, for example? Please don't ask me to read other articles as I've already been referred to them all and none of them answer my questions. I cant find any definitive information on this issue anywhere. If someone could be clear and concise about exactly how i pay my taxes for the above scenario, it would be much appreciated. Many thanks!

Can anyone help with this please? Thanks.

Hi _viator,
The banks and building societies submit the untaxed interest details to HMRC after the tax year end.
Once received we will review the tax year and if underpaid a calculation will be issued with the details.
If the underpayment is less than £3000 and your PAYE income is large enough to collect the underpayment your tax code would be amended in the following tax year to collect.
We would use the untaxed interest figures supplied as an estimate going forward and your tax code would be adjusted.
f your untaxed interest changes you can contact HMRC to amend the code Income Tax: general enquiries
Thank you.