Rental income tax affects every UK landlord, from those with a single buy-to-let property to large portfolio owners. Understanding how this tax works is crucial for managing your property business effectively and avoiding costly mistakes.
This guide explains everything you need to know about rental income tax in the UK, including current rates, allowable expenses, and the impact of Section 24 mortgage interest restrictions.
How Rental Income Tax Works in the UK
Rental income tax is charged on your net rental profit, not your gross rental income. This means you can deduct allowable expenses before calculating your tax liability.
Your rental income is added to your other income (salary, dividends, pensions) and taxed at your marginal rate. For the 2025/26 tax year, the rates are:
- Basic rate: 20% (income up to £37,700)
- Higher rate: 40% (income between £37,700 and £125,140)
- Additional rate: 45% (income over £125,140)
For example, a landlord earning £30,000 from employment plus £15,000 net rental profit would pay 20% tax on £7,700 of rental income (the amount above the basic rate threshold) and 40% on the remaining £7,300.
Allowable Expenses for Rental Income Tax
You can deduct legitimate business expenses from your rental income before calculating tax. Common allowable expenses include:
- Letting agent fees and property management costs
- Insurance premiums
- Repairs and maintenance (not improvements)
- Advertising for tenants
- Legal and professional fees
- Accountancy fees
- Ground rent and service charges
- Utility bills when property is vacant
The key rule is that expenses must be "wholly and exclusively" for your rental business. Personal expenses or improvements that add value to the property are not allowable.
Capital vs Revenue Expenses
Understanding the difference between capital and revenue expenses is crucial for rental income tax calculations:
- Revenue expenses: Day-to-day running costs that can be deducted from rental income (repairs, insurance, management fees)
- Capital expenses: Improvements or enhancements that cannot be deducted immediately (new kitchen, extension, structural work)
Capital expenses may qualify for capital allowances or can be offset against capital gains when you sell the property.
Section 24 Mortgage Interest Restriction
Since April 2020, the Section 24 rules have significantly changed how mortgage interest is treated for rental income tax purposes. This affects individual landlords but not companies.
Under Section 24, you cannot deduct mortgage interest as an expense. Instead, you receive a basic rate tax credit (20%) on your mortgage interest payments.
Here's how it works in practice:
Example: A higher-rate taxpayer with £20,000 rental income and £8,000 mortgage interest:
- Rental income: £20,000
- Other expenses: £2,000
- Taxable rental profit: £18,000 (mortgage interest not deducted)
- Tax at 40%: £7,200
- Less basic rate credit (20% of £8,000): £1,600
- Final tax liability: £5,600
This restriction often makes incorporation attractive for landlords with significant mortgage interest payments.
Property Allowance and Rent-a-Room Relief
Two reliefs can help reduce your rental income tax liability:
Property Allowance
The property allowance gives you a £1,000 tax-free allowance on property income. You can either:
- Claim the £1,000 allowance instead of deducting expenses (only worthwhile if expenses are less than £1,000)
- Deduct actual expenses and ignore the allowance
Rent-a-Room Relief
If you rent out a room in your main home, you can earn up to £7,500 per year tax-free under rent-a-room relief. This applies to live-in arrangements only.
Calculating Your Rental Income Tax
Follow these steps to calculate your rental income tax liability:
- Add up all rental income received during the tax year
- Deduct all allowable expenses (except mortgage interest for individuals)
- Calculate your net rental profit
- Add this to your other income to find your total income
- Apply the appropriate tax rates
- Deduct any basic rate credit for mortgage interest (individuals only)
For complex calculations involving multiple properties or significant expenses, consider using professional calculators or seeking specialist advice.
Record Keeping and Compliance
HMRC requires landlords to keep detailed records of all rental income and expenses. You must retain:
- Rental agreements and rent rolls
- Bank statements showing rent received
- Receipts for all expenses
- Insurance policies and certificates
- Professional fee invoices
Records must be kept for at least five years after the submission deadline for the relevant tax return.
Making Tax Digital (MTD) Changes
From April 2026, landlords with rental income over £10,000 will need to submit quarterly updates to HMRC under Making Tax Digital for Income Tax (ITSA). This will require digital record-keeping and compatible software.
Start preparing now by digitising your records and considering whether you need professional support for compliance.
When to Seek Professional Help
Consider getting specialist advice if you:
- Own multiple properties or have complex arrangements
- Are considering incorporation to reduce tax
- Have significant mortgage interest payments affected by Section 24
- Need help with MTD compliance
- Want to optimise your tax position legally
Professional services can often save more in tax than they cost, especially for landlords with substantial portfolios or higher-rate tax exposure.