A useful rental-property budget starts with records, not a promise that costs can always be cut. Repairs, insurance, utilities and management charges vary with the building, tenancy and services provided. A landlord can compare them only after recording what was actually paid and why.
Keep a simple record for each property
Create a separate folder or ledger for every rental. Record the date, supplier, amount, property, reason for the payment and how it was paid. Keep invoices, receipts, contracts, bank entries and relevant messages together. Note which tenancy or repair a cost relates to. HMRC says landlords should keep records of rental dates, income, receipts, invoices, bank statements and allowable expenses. Good records make it easier to answer questions and prepare an accurate return.
Group costs by purpose
A practical list might include maintenance and repairs, buildings or landlord insurance, agent and management fees, utilities or council tax paid by the landlord, cleaning or gardening services, advertising and direct administration costs. Add a short note if a bill covers more than one property or includes private use, and keep the calculation showing how the rental share was worked out. Record insurance payments and any claim settlement separately; do not assume that the same loss can be counted twice.
Separate repair work from improvements
Keep the contractor’s quote, invoice and description of the work. HMRC distinguishes repairs that restore an asset from capital improvements. Its examples of repairs include replacing storm-damaged roof tiles or a broken boiler, while an improvement may be treated differently for tax. The label on an invoice is not decisive: the nature of the work and property’s condition matter. Ask a qualified tax adviser if a project combines repair and improvement or the treatment is uncertain.
Do not treat every mortgage payment as a running cost
Record mortgage interest and capital repayments separately. Tax treatment depends on the property, ownership and taxpayer. HMRC’s rules for residential property income are not the same as simply deducting the whole monthly mortgage payment. Avoid using a generic online percentage to estimate what is deductible.
Review the ledger periodically
Compare the budget with actual invoices, flag overdue safety or repair work, and check that insurance and service contracts still match the property. This is a way to spot missing records or unexpected bills, not a guarantee of lower costs or higher returns. Keep records for the period HMRC requires and get advice if you are unsure what to retain or claim.
Further reading: HMRC, Work out your rental income: https://www.gov.uk/guidance/income-tax-when-you-rent-out-a-property-working-out-your-rental-income ; HMRC, Keeping rental income records: https://www.gov.uk/keeping-your-pay-tax-records/rental-income ; GOV.UK, Landlord repairs: https://www.gov.uk/renting-out-a-property/making-repairs . Guidance checked 26 October 2026.