GUIDE · LEASEHOLD COSTS · Last reviewed August 2026

Service charge red flags before you offer on a flat

Property portals don't require service charges to be listed. Here's what to actually check before you commit — and what patterns suggest costs are about to rise.

Service charge is one of the biggest hidden variables in buying a leasehold flat — and unlike the mortgage payment, it's rarely front and centre when you're viewing a property. It's not optional, it's not usually negotiable, and it can move significantly year to year.

Where to actually find the figure

What a Section 20 notice means Landlords/management companies must formally notify leaseholders before carrying out major works costing over a set threshold per leaseholder. If a building has an active or recent Section 20, ask exactly what it covers and what your specific share would be — this is one of the most common surprise costs in leasehold buying.

Red flags that suggest rising costs ahead

Ground rent — check this separately

Ground rent is a separate charge from service charge, paid to the freeholder. Older leases sometimes have escalating ground rent clauses (doubling every 10 years, for example) which can make a flat very hard to mortgage or resell later. Always check the exact clause, not just the current amount — see our glossary for how this differs from service charge, and our 2026 reform guide for how ground rent rules are changing. This is a particularly common issue on ex-local-authority flats, where management and billing can be less predictable.

Factor real running costs into what you can afford

Homabu's calculator adds an estimated service charge to your monthly cost, so you see the true number — not just the mortgage payment.

Try the calculator →