Untaxed Interest on Savings and Investments

My wife has not worked for a few years and we are fortunate to have a decent amount of savings. The interest she earned was below her personal allowance. However, we have both started to take personal pensions (our state pensions start next year) and she will now be having to pay tax. Is there an easy way to reconcile the figure of untaxed interest on savings shown on the "How we worked out your tax code" calculation in her Gateway account please? I know it is an estimate but I'd like to know how it has been calculated. Thank you

Hi,
The untaxed savings income included in your tax code is a estimated figure carried forward from a previous tax year.
We check if the tax you have paid is correct once we get the actual savings income details from the banks, this happens automatically once the tax year has ended.
If you require a breakdown of how the untaxed interest has been calculated please contact the helpline.
Income Tax: general enquiries
Thank you.

Say I have a pension of £6000 and taxable savings interest £6000 and £7570 share dividends for financial year 23/24. Can I assume that my savings interest is covered by the 5k 'Starting Rate' and 1k 'Personal savings allowance? Therefore no tax to pay on my savings interest? Further, can I assume that my pension 'wages ' of only 6k allows me to use £12570-6000= £6570 of my 'Standard Personal Allowance to offset against my £7570 dividends? If yes, this would leave me with £7570-6000 = £1000 taxable dividends, but then I apply £1k dividend allowance which will leave me £0 dividend tax to pay. Is the above a correct assumption?

Hi,
Unfortunately, it is not possible to check individual tax records through this forum. If you have a question which relates to your personal tax situation or tax code please contact our Income Tax team. 
https://www.gov.uk/government/organisations/hm-revenue-customs/contact/income-tax-enquiries-for-individuals-pensioners-and-employees
Thank you.