Rental income tax is one of the most misunderstood areas of personal finance for UK landlords. Between Section 24 mortgage interest restrictions, the shift to Making Tax Digital, and a maze of allowable expenses, it is easy to overpay HMRC or miss a legitimate deduction. With around 2.7 million private landlords in the UK, the stakes are high. This guide cuts through the confusion and gives you practical, up-to-date strategies to keep more of your rental income while staying fully compliant in 2026.
Table of Contents
- Understand how rental income is taxed
- Claim every allowable expense
- Get to grips with Section 24 and mortgage interest changes
- Don't overlook the property allowance
- Get ready for Making Tax Digital 2026
- When to seek expert help
- Take the next step: make tax easy with VoxaMTD
- Frequently asked questions
Key Takeaways
| Point | Details |
|---|---|
| Claim all expenses | Deductions for repairs, management fees, insurance and travel add up to major savings. |
| Understand Section 24 | Mortgage interest can only be offset through a 20% tax credit for individuals, not full deduction. |
| Use the property allowance | Landlords with under £1,000 expenses can opt for the tax-free property allowance instead. |
| Prepare for MTD 2026 | Switch to digital records and MTD-compliant software now to avoid stress and penalties. |
Understand how rental income is taxed
Before you can save tax, you need to understand how HMRC calculates what you owe. Your taxable rental profit is simply your total rental income minus your allowable expenses. That profit is then added to any other income you earn, such as a salary or pension, and taxed at the relevant rate.
The tax rates on rental profit are 20% at the basic rate, 40% at the higher rate, and 45% at the additional rate. Because rental income stacks on top of your other earnings, many landlords find themselves pushed into a higher tax band without realising it. That makes accurate expense tracking essential, not optional.
Here is a quick summary of your core obligations:
- Calculate rental profit by deducting allowable expenses from gross rental income
- File a Self Assessment tax return annually, with the deadline on 31 January following the tax year
- Pay any tax owed by the same 31 January deadline
- Keep digital records if you are approaching MTD thresholds
Missing rental tax deadlines triggers automatic penalties, starting at £100 for a late return. Getting organised early is the simplest way to avoid unnecessary fines.
Claim every allowable expense
This is where many landlords leave money on the table. HMRC allows you to deduct costs that are wholly and exclusively for your rental business, and the list is broader than most people realise.
Allowable expenses typically include:
- Repairs and maintenance (fixing a broken boiler, repainting walls, replacing a damaged fence)
- Letting agent fees and property management charges
- Buildings and contents insurance premiums
- Utility bills and council tax if you pay them on behalf of tenants
- Professional fees such as accountancy, legal advice, and surveyor costs
- Travel and mileage to visit your rental property (45p per mile for the first 10,000 miles)
- Service charges and ground rent on leasehold properties
The single most common mistake is confusing repairs with improvements. Replacing a broken window is a repair and is fully deductible. Replacing all windows with double glazing where there were none before is an improvement and is not deductible against income tax (though it may qualify for capital allowances on disposal).
"If in doubt, ask yourself: am I restoring something to its original condition, or am I making it better than it was? The former is a repair; the latter is an improvement."
Pro Tip: Keep a dedicated folder, physical or digital, for every receipt related to your rental property. Good landlord finance tips consistently point to record-keeping as the single biggest factor in maximising legitimate deductions at year end.
Get to grips with Section 24 and mortgage interest changes
Section 24 is the tax change that has hit private landlords hardest over the past few years, and its effects are still catching people out. Before 2017, you could deduct your full mortgage interest from rental income before calculating tax. That relief has been completely phased out for individual landlords.
Now, instead of a full deduction, you receive a 20% tax credit on your mortgage interest. So if you pay £5,000 in mortgage interest, you get a £1,000 credit against your tax bill, not a £5,000 reduction in your taxable profit. For higher-rate taxpayers, this is a significant difference.
Here is a simple comparison to illustrate the impact:
| Scenario | Old rules (pre-2017) | New rules (Section 24) |
|---|---|---|
| Rental income | £18,000 | £18,000 |
| Mortgage interest | £8,000 | £8,000 |
| Taxable profit | £10,000 | £18,000 |
| Tax at 40% | £4,000 | £7,200 |
| Less 20% credit | N/A | £1,600 |
| Tax payable | £4,000 | £5,600 |
Limited companies are not affected by Section 24 and can still deduct mortgage interest in full. This is why many landlords with larger portfolios have considered incorporation, though the costs and stamp duty implications must be weighed carefully. Understanding the full MTD digital submission process also becomes more important when your taxable profit figures change significantly under Section 24.
Don't overlook the property allowance
If your rental income is modest, there is a simpler option available. The £1,000 property allowance lets you earn up to £1,000 in rental income each tax year completely tax-free, with no need to file a Self Assessment return at all.
Here is how to decide which approach suits you:
- Add up your actual allowable expenses for the tax year
- Compare that total to £1,000 — whichever is higher gives you the better deduction
- Choose actual expenses if they exceed £1,000, as you cannot combine both methods
- Use the property allowance if your expenses are low and your income is under £1,000
- Carry forward any net losses from a rental property to offset future profits
The property allowance of £1,000 is particularly useful for landlords who rent out a single room or a small property with minimal running costs. It removes the administrative burden of tracking every expense.
Pro Tip: If you are unsure which method saves you more, run both calculations before submitting. Reviewing your account reconciliation steps at the end of each quarter makes this comparison straightforward rather than a last-minute scramble in January.
Get ready for Making Tax Digital 2026
Making Tax Digital for Income Tax Self Assessment (MTD for ITSA) is the biggest structural change to UK tax compliance in a generation. From 6 April 2026, landlords with qualifying gross income above £50,000 must keep digital records and submit quarterly updates to HMRC using MTD-compliant software.
The rollout is phased by income threshold:
| Phase | Start date | Income threshold |
|---|---|---|
| Phase 1 | 6 April 2026 | Over £50,000 |
| Phase 2 | 6 April 2027 | Over £30,000 |
| Phase 3 | 6 April 2028 | Over £20,000 |
Approximately 864,000 landlords fall into Phase 1 alone. Quarterly submission deadlines run as follows: Quarter 1 (April to June) is due by 31 August, Quarter 2 (July to September) by 30 November, Quarter 3 (October to December) by 28 February, and Quarter 4 (January to March) by 31 May. A final end-of-period statement then replaces the traditional Self Assessment return.
The 2026/27 tax year includes a soft landing period, meaning HMRC will not issue penalties for late quarterly submissions during the first year. However, that grace period will not last. Understanding MTD terms explained now will save you considerable stress later.
For a full breakdown of what landlords need to do, the MTD for landlords guidance from The Independent Landlord is a useful reference.
Pro Tip: Do not wait until April 2026 to switch to digital record-keeping. Starting now means your first quarterly submission will feel routine rather than rushed.
When to seek expert help
Digital tools handle a great deal, but there are situations where professional advice pays for itself many times over. Some landlords prefer accountants for multi-property or complex cases, and it is easy to see why.
Consider speaking to a tax adviser if you:
- Own multiple properties with different ownership structures
- Are considering incorporating your portfolio into a limited company
- Have received a letter from HMRC about an investigation or compliance check
- Are unsure whether a cost qualifies as a repair or an improvement
- Have income from overseas property or mixed-use assets
- Are approaching an MTD threshold for the first time
"An accountant does not just file your return. A good one spots deductions you missed, flags risks before they become problems, and saves you more than their fee."
For landlords who want professional oversight without the traditional accountancy price tag, the accountant portal solutions at VoxaMTD connect you with qualified professionals who work directly within the platform. This means your records, submissions, and reviews all happen in one place.
Take the next step: make tax easy with VoxaMTD
You now have a clear picture of how rental income is taxed, which expenses to claim, how Section 24 affects your bill, and what MTD compliance requires. The next step is putting that knowledge into a system that works automatically.
VoxaMTD for landlords is a free, HMRC-recognised platform that handles quarterly MTD submissions, imports your bank transactions automatically, and uses AI to categorise your expenses. The built-in Section 24 calculator shows exactly how mortgage interest affects your tax position, and Alex AI Accountant is available 24/7 to answer your tax questions by voice. If you want a human expert in the loop, the Professional tier at £30/month includes quarterly reviews with a real accountant. Start for free at VoxaMTD and make 2026 the year your rental tax works for you, not against you.
Frequently asked questions
What counts as an allowable expense for rental income tax?
Any cost that is wholly and exclusively for running your rental business qualifies, including repairs, letting agent fees, insurance, and travel to the property.
How does Section 24 affect my mortgage interest deduction?
You now receive a 20% tax credit on mortgage interest paid rather than deducting the full amount from your rental profits, which increases taxable income for higher-rate taxpayers.
When must landlords comply with Making Tax Digital?
Landlords with over £50,000 in gross rental income must use MTD-compliant software from 6 April 2026, with lower thresholds of £30,000 and £20,000 phased in during 2027 and 2028 respectively.
Can I use the property allowance if I have expenses over £1,000?
No. You must choose one method or the other. If your actual expenses exceed £1,000, claiming those will give you a larger deduction and you cannot combine both approaches.