Contact

Email: contact@isasums.co.uk. A person reads every message.

Our figure differs from HMRC's

Tell us the tax year, your income before tax, the interest your bank reported and the figure in HMRC's letter or tax code notice. The usual reasons for a gap are interest you forgot (a second account, a joint account split in two, a bond that matured), a tax code that collects an estimate rather than the final figure, and pension or Gift Aid relief that widens your basic rate band. If an official rule has changed, we update the parameter file, rerun the tests and date the change.

What we cannot do

We cannot see your accounts, your ISA subscriptions or your tax record, open or transfer an ISA, or speak to HMRC, NS&I or a bank for you. Please do not send account numbers, your National Insurance number or your address. For your own tax position, HMRC's helpline and your personal tax account are the place to go; for guidance on where to save, MoneyHelper is free and impartial.

Using the calculator on your own site

Credit unions, money guidance charities, pensioners' groups and personal finance writers can show the ISA against taxable account calculator in an iframe at no cost. The code and the conditions are on the embed page.

Publisher

Radif Partners
49 rue du Ressort
63000 Clermont-Ferrand, France
contact@isasums.co.uk

Updated: 2026-10-19.