Do I need to fill in a tax return as a landlord?

Yes — if your annual rental income exceeds £1,000 (the property income allowance) and you're not using that allowance, you must report it to HMRC via a Self Assessment tax return. Even if your expenses exceed your income and you make a loss, you still need to tell HMRC. If this is your first time renting out property, you need to register for Self Assessment by 5 October following the tax year.

Which Self Assessment pages do I fill in for rental income?

You need the SA105 (UK Property) supplementary pages, plus the main SA100 tax return. If you have overseas rental property, you need SA106 instead. The SA105 covers your rental income, allowable expenses, and calculates your property profit or loss. If you receive rental income from a jointly owned property, you each report your share on your own return.

Can I deduct mortgage interest on my rental property?

Residential landlords cannot deduct mortgage interest as an expense. Instead, you receive a 20% tax credit on your mortgage interest costs (Section 24 restriction). This means higher-rate taxpayers pay more tax than they did before the restriction was introduced. The tax credit is entered in box 44 of the SA105. Commercial property landlords can still deduct the full mortgage interest.

What is the deadline for my landlord tax return?

If filing online, the deadline is 31 January following the end of the tax year (e.g. 31 January 2028 for the 2026/27 tax year). Paper returns must be filed by 31 October. Any tax owed must be paid by 31 January too. If you owe more than £1,000 in tax, HMRC may require Payments on Account — two advance payments toward next year's tax bill.

What expenses can landlords claim on tax return?

Common allowable expenses include: letting agent fees, landlord insurance, property repairs (not improvements), legal fees for tenancy matters, advertising costs, accountant fees, travel to the property, and utilities if you pay them. You cannot claim for mortgage interest as an expense (residential), capital improvements, or your own labour.

What is the difference between a repair and an improvement?

A repair restores something to its original condition and is tax-deductible. An improvement makes it better than before and is not deductible (but may reduce capital gains tax when you sell). Fixing a broken boiler = repair. Installing a boiler where none existed = improvement. Replacing worn carpet = repair. Upgrading carpet to hardwood = improvement.

Landlord Tax Return Guide — Self Assessment Property Pages Step by Step | PocketWise

Landlord Tax Return Guide — Self Assessment Property Pages Step by Step

How to complete the property pages of your Self Assessment tax return as a UK landlord — reporting rental income, claiming expenses, and avoiding common mistakes.

By PocketWise · 25 March 2026 · 6 min read

Filling in your first Self Assessment tax return as a landlord can feel overwhelming. Between rental income calculations, expense deductions, the Section 24 mortgage interest restriction, and Payments on Account, there’s a lot to get your head around.

The stakes are real: get it wrong and you could face HMRC penalties, pay more tax than you should, or miss valuable deductions you’re entitled to. Many landlords overpay simply because they don’t know what expenses they can claim or misunderstand how mortgage interest relief now works.

The good news is that once you understand the structure, completing the SA105 (UK Property) pages becomes straightforward. This guide walks you through every box, explains what you can and can’t deduct, shows you how to calculate your taxable profit correctly, and helps you avoid the common mistakes that trigger HMRC enquiries.

Whether you’re a first-time landlord or have been letting property for years but still find tax returns confusing, this step-by-step guide will help you complete your return confidently and correctly.

Do You Need to File?

Situation	Need to file?
Rental income over £1,000/year	Yes — register for Self Assessment
Rental income under £1,000/year	No — covered by the £1,000 property income allowance
Using the property income allowance	No — but you can’t also claim expenses
Made a rental loss	Yes — must be reported to carry it forward
Rent-a-Room income under £7,500/year	No — exempt under Rent a Room scheme
Overseas rental property	Yes — use SA106 instead of SA105
Joint property ownership	Yes — each owner reports their share

Key Dates

Deadline	Date
Register for Self Assessment	5 October following the tax year
Paper return deadline	31 October following the tax year
Online return deadline	31 January following the tax year
Tax payment deadline	31 January following the tax year
Payments on Account (1st)	31 January
Payments on Account (2nd)	31 July

Step-by-Step: Completing SA105 (UK Property)

Section 1: Property Income

Box	What to enter	Notes
Box 1	Total rents and other income from property	Gross rental income for the tax year
		Include rent, ground rent received, service charges received
		Don’t include the deposit (unless you kept it as income)

How to Calculate Rental Income

Include	Don’t include
Rent received from tenants	Tenant deposits (held for return)
Rent owed but not yet received (accruals basis)	Deposits kept as income — these ARE included
Service charges received	Insurance claim payouts (capital)
Ground rent received	Sale of the property (this is CGT, not income)
Income from furnished holiday lets (if applicable)

Section 2: Property Expenses

Box	Expense type	Examples
Box 2	Rent, rates, and insurance	Ground rent, council tax (if you pay it), landlord insurance
Box 3	Property repairs and maintenance	Plumber, electrician, redecoration, replacing broken items
Box 4	Finance costs (non-residential only)	Mortgage interest on commercial property only
Box 5	Legal, management, and other professional fees	Letting agent fees, accountant, solicitor for tenancy disputes
Box 6	Cost of services provided	Cleaning, gardening, communal area maintenance
Box 7	Travel	Journeys to the property for management/repairs
Box 8	Other allowable expenses	Advertising for tenants, stationery, phone calls

Allowable Expenses — Full List

Expense	Deductible?	Notes
Letting agent fees	Yes	Monthly management fee, tenant find fee
Landlord insurance	Yes	Buildings, contents, liability, rent guarantee
Ground rent	Yes	Leasehold properties
Service charges	Yes	If you pay them as landlord
Council tax	Yes	Only if you pay it (not if the tenant pays)
Utility bills	Yes	Only if you pay them (e.g. HMO)
Repairs and maintenance	Yes	Fixing, repairing, redecorating
Replacing furnishings	Yes	Replacement of Domestic Items Relief
Accountant fees	Yes	For property tax work
Legal fees (letting-related)	Yes	Drafting tenancy agreement, eviction costs
Advertising for tenants	Yes	Online listings, signage
Travel to property	Yes	Mileage or public transport for management visits
Phone and stationery	Yes	Reasonable proportion for property management
Mortgage interest (residential)	No — tax credit only	See Section 24 below
Mortgage interest (commercial)	Yes	Full deduction
Capital improvements	No	Adding something new is not a repair
Your own labour	No	You can’t charge for your own time
Pre-letting expenses	Partly	Only if incurred within 7 years of first letting

Repairs vs Improvements

Repair (deductible)	Improvement (NOT deductible)
Fixing a broken boiler	Installing a new boiler where none existed
Repainting walls	Knocking walls down to create open-plan
Replacing broken windows with like-for-like	Upgrading single glazing to double glazing
Fixing a leak in the roof	Adding a loft conversion
Replacing worn carpet with similar quality	Upgrading carpet to hardwood flooring
Replacing a broken washing machine	Adding a dishwasher for the first time

Principle: A repair restores to its original condition. An improvement makes it better than before.

Section 3: Mortgage Interest Tax Credit (Section 24)

Box	What to enter
Box 44	Total residential finance costs (mortgage interest, loan interest, arrangement fees)

This is NOT deducted as an expense. Instead, you receive a 20% tax credit on this amount.

Section 24 Impact by Tax Band

Tax band	Effect
Basic rate (20%)	No change — 20% relief matches 20% tax rate
Higher rate (40%)	You pay 40% tax but only get 20% relief — net cost of 20% on mortgage interest
Additional rate (45%)	You pay 45% tax but only get 20% relief — net cost of 25% on mortgage interest

Section 4: Calculating Profit or Loss

Calculation	Formula
Total income (Box 1)	e.g. £12,000
Minus total expenses (Boxes 2–8)	e.g. £4,000
= Taxable profit	e.g. £8,000
Minus loss brought forward	From previous years
= Net profit	Taxable amount
Tax credit (Box 44 × 20%)	Reduces your tax bill (not your taxable income)

Example: Complete Tax Calculation

Item	Amount
Annual rent received	£12,000
Letting agent fee (10%)	–£1,200
Insurance	–£300
Repairs	–£800
Other expenses	–£200
Taxable profit	£9,500
Mortgage interest paid	£4,000
Tax credit (20% of £4,000)	–£800

If basic rate taxpayer	Calculation
Tax on £9,500 at 20%	£1,900
Less Section 24 credit	–£800
Tax to pay	£1,100

If higher rate taxpayer	Calculation
Tax on £9,500 at 40%	£3,800
Less Section 24 credit	–£800
Tax to pay	£3,000

Common Mistakes to Avoid

Mistake	Consequence
Not registering for Self Assessment	Late registration penalties
Deducting mortgage interest as an expense (residential)	Incorrect return — HMRC will correct and may charge penalties
Claiming improvements as repairs	HMRC can disallow and charge interest
Not reporting void periods correctly	Income only includes rent actually due, not void months
Forgetting Payments on Account	Unexpected cash flow demand in January and July
Not keeping records	Must keep records for 5 years after the filing deadline

Record-Keeping

Record	Keep for
Rental income records (bank statements, tenant payments)	5 years after filing deadline
Expense receipts and invoices	5 years
Mortgage statements	5 years
Tenancy agreements	Duration of tenancy + 5 years
Inventory and condition reports	Duration of tenancy + 5 years
Insurance policies	5 years