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Find out more'I've accidentally paid too much tax'
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I rent out a property and fill in self-assessment tax returns.
For the past few years while filling these out, I haven’t entered the value of mortgage interest I pay on the property, as I believed I couldn’t use it to reduce my tax bill.
I’ve recently learnt I was wrong. Is it now too late to add it?
Simon from Oxfordshire
'It's not too late to claim this tax credit'
Mike Croxford, Which? Money expert, says...
Fortunately, you can change your recent tax returns after submitting them.
To recap: mortgage interest on rental properties used to be treated like any other tax-deductible expense, but this changed with a phased adjustment that started in April 2017 and was fully implemented by the start of the 2020-21 tax year.
Previously higher-rate taxpayers could effectively receive 40% tax relief on the mortgage interest, whereas basic-rate taxpayers only got 20%. Now all landlords receive the same tax credit worth 20% of the amount of their mortgage interest and this is subtracted from your final tax bill.
You are allowed to revise and claim a refund for up to the past four tax years
To claim it, you enter the full amount of interest paid into box 44 on the HMRC SA105 form.
If you want to change the submission for the 2023-24 tax year, you can do this online by 31 January 2026 or by posting a revised paper tax return.
You are allowed to revise and claim a refund for up to the past four tax years. If you wish to change returns for the 2022-23, 2021-22, or 2020-21 tax years, you simply write in with a full explanation to HMRC.
Full details on amending your tax return are available on the government's website.
- Find out more: Buy-to-let mortgage interest tax relief explained
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