Calculator · updated 10 November 2026
Rental profit calculator
See what a rental property really makes once every cost is counted, monthly and yearly, before tax.
Key facts
- Count empty weeks: two to four a year is a common allowance.
- Full management agents typically charge a percentage of the rent; check your agreement.
- Mortgage interest reduces your cash but, for tax, gets a 20% credit (24% from 2027/28) rather than a deduction.
- Use the profit before interest in the landlord tax calculator to see your tax.
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Monthly cash after costs (before tax)
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Rent received in the year–
Running costs–
Profit before interest (taxable)–
Yearly cash before tax–
Profit vs cash
Profit before interest is the figure HMRC taxes, because mortgage interest isn't deducted under Section 24. Cash is what's actually left after paying the mortgage interest. A property can have small cash flow but a sizeable taxable profit. Run the profit figure through the landlord tax calculator.
Costs landlords often forget
- Empty periods and re-letting fees between tenants.
- Gas safety every year, an EICR every five years, an EPC every ten.
- Replacing worn furniture and appliances.
- Upgrades to reach EPC C by 1 October 2030.
- Accountancy and Making Tax Digital software.
Frequently asked questions
What is a good monthly profit on a buy-to-let?
It depends on your aims. Many landlords look for positive cash after all costs plus a safety margin for rate rises and repairs.
Are capital repayments a cost?
No. They reduce your loan but aren't an expense for profit or tax.
Sources
- GOV.UK: Work out your rental income when you let property
- GOV.UK: Tax relief for residential landlords, how it's worked out
- GOV.UK: Minimum energy efficiency standard, landlord guidance
Sources last checked 10 November 2026. See all our sources and how we keep pages up to date.