Am I Overpaying Tax on My Rental Income? A 5-Minute Self-Assessment
Five minutes from now, you will know if you are overpaying
Five minutes from now, you will know if you are overpaying tax on your rental income.
No accountancy jargon. No complex forms. Just a clear self-assessment that tells you where you stand.
Most landlords never do this. They file their return, pay what HMRC asks, and never question if it is right. That is exactly how overpaying happens.
The Self-Assessment
Answer these five questions honestly. Each one represents a common overpayment trap.
Question 1: Have you reviewed your tax position in the last 3 years?
If you bought your property before 2020 and have not reviewed your tax since, the answer is almost certainly yes. You are overpaying.
Section 24 rules changed in 2017. If you have not recalculated your position since, your tax filings are likely wrong. Either you are paying too much or, more dangerously, too little.
Question 2: Do you deduct your full mortgage interest as an expense?
If you answered yes, you need to read this carefully.
Higher and additional rate taxpayers cannot deduct the full mortgage interest. Section 24 restricts relief to 20% only. If you are a 40% taxpayer deducting the full 10,000 pounds interest on a 200,000 pound mortgage, you are overpaying tax by approximately 2,000 pounds per year.
Basic rate taxpayers are not affected by Section 24 restrictions. But most landlords think they are deducting correctly when they are not.
Question 3: Do you claim all allowable expenses?
Most landlords miss at least one of these:
- Capital allowances on fixtures and fittings (washing machines, carpets, boilers)
- Legal fees for tenancy agreements (not just eviction)
- Professional cleaning between tenancies
- Insurance (buildings and contents for rental property)
- Property agent fees (letting and management)
- Accountancy fees (specifically for tax return preparation)
If you have been claiming none of these, or only some, you are likely overpaying.
Question 4: Have you claimed the wear and tear allowance correctly?
The old wear and tear allowance (10% of rent) was replaced in 2016 with a new system. You can now only claim for items you actually replaced.
If you are still using the 10% shortcut, you are likely claiming the wrong amount. Either too much or too little.
Question 5: Do you use a general accountant or a property specialist?
General accountants handle business accounts, personal tax, and everything in between. Property tax is a specialist area. The rules are different, the deductions are different, and the expertise matters.
If you use a general accountant for your landlord tax, you are likely overpaying. Not because they are bad. Because they do not focus on this area.
The Scoring
Count your answers:
What Overpaying Actually Looks Like
Here is a real example:
Sarah, higher rate taxpayer:
- Two properties, combined rent 22,000 pounds per year
- Believed she was deducting correctly
- Overpaying by 3,200 pounds per year because she was deducting full mortgage interest instead of applying Section 24 restriction
- Three years of overpayment: 9,600 pounds plus HMRC interest
The fix: Recalculate under Section 24 rules. Claim back overpaid tax via amendment. Budget correctly going forward.
Why HMRC Has Not Told You
HMRC does not point out when you are overpaying. They only tell you when you are underpaying.
This is not malicious. It is just how the system works. They process your return, collect what you owe, and move on. They do not audit correct returns. They audit returns that look wrong.
If you are overpaying, HMRC is not going to refund you unless you ask.
The Right Move
Download your last three tax returns.
Use our Landlord Tax Calculator to estimate your correct tax position.
If the numbers do not match, speak to a property tax specialist.
If you find overpayment, claim it back via amendment. You have four years.
The average landlord overpays by 2,000 to 5,000 pounds per year. Most will never know.
Get clear on where you stand
Get your estimated landlord tax position in minutes. No signup. No jargon. Just numbers.