Tax on Interest income only

Your example on https://www.gov.uk/apply-tax-free-interest-on-savings include employment income. When you don't have any income from any other sources except savings interest, how much tax will have to be paid on annual savings interest income (only) of £15000/- please ? How did you work that out ?

Hi V Khandekar,
If you only receive income from savings interest, your £12570 of tax free allowances will be applied against this first.
The maximum Savings allowance of £5000 will then be applied (as there are no wages or pension income to reduce this Savings allowance).
As a result, if your annual savings interest income is £15000, no tax will be due on this savings income.
Thank you.