Short answer: No law in England says your boiler must be serviced before you sell. But the property information form most conveyancers use asks about the central heating and when it was last serviced, and buyers' surveyors note the boiler. A recent service record, the installation certificate and any warranty paperwork make questions easier to answer.
When you are selling a home in London, the boiler can become a surprising sticking point. There is no legal duty to service it before sale, but buyers, surveyors and solicitors all ask questions about it.
What the law says
There is no law in England that requires a boiler service before a house or flat is sold. There is also no legal requirement for a “boiler certificate” to sell, in the way an Energy Performance Certificate is needed.
What does exist is paperwork from the installation. When a new gas boiler is fitted, the Gas Safe registered installer notifies building control through the Gas Safe Register, and a building regulations compliance certificate is sent to the householder. Buyers’ solicitors often ask for this, especially if the boiler is fairly new.
What the property forms ask
In England, most sellers fill in a property information form for their conveyancer, usually the Law Society’s TA6. It has a section on services and asks about the central heating system, including whether it has been serviced and when it was last serviced. If you are not sure of the date, you may have to say you do not know, which can prompt the buyer’s solicitor to ask more.
If you are selling a leasehold flat, there may be extra questions about the boiler and gas supply, and your lease may include a clause about servicing.
What buyers’ surveyors look for
A buyer’s surveyor will usually note:
- The boiler’s make and approximate age
- Its general condition
- Any visible issues, such as staining, corrosion or flue position
- Whether servicing records are available
Surveyors rarely test the boiler in depth. Most reports advise the buyer to have the heating checked by a Gas Safe registered engineer before exchange. Some buyers do, and any faults found can become part of price talks.
Why a recent service helps
A service record from the last 12 months gives you a straightforward answer to the form question. It shows the boiler was checked, what condition it was in, and the combustion readings. It also means any faults have already been found and, ideally, fixed.
In family areas like Wimbledon, where many Edwardian houses have system boilers with unvented cylinders, buyers often ask about the cylinder too. A record showing the cylinder safety valves were checked is useful. Our Wimbledon area page covers the housing there.
Paperwork to gather
| Document | Where to find it |
|---|---|
| Building regulations compliance certificate | Sent after installation, or request from Gas Safe Register |
| Benchmark checklist | Back of the boiler installation manual |
| Service records | Your files, the engineer, or a sticker inside the boiler case |
| Warranty registration | Maker’s website or confirmation email |
| Unvented cylinder records | Cylinder manual or service records |
| Landlord gas safety records (if let) | Your files or lettings agent |
If you cannot find the service history, our post on finding your boiler service history explains where else to look.
Warranty and the buyer
If your boiler is still in its maker’s guarantee period, that is a selling point. Many guarantees stay with the boiler, but some makers need the new owner to register or let them know. Check the terms. A buyer may also want proof that yearly services were done, because most makers make that a condition. Worcester Bosch, for example, says yearly servicing must be completed each year to keep its guarantee valid.
Our post on missed services and warranties explains what each maker says.
If you are buying
If you are on the buying side, ask the seller’s solicitor for:
- The date of the last service and a copy of the record
- The installation compliance certificate
- Warranty details
- For a rented flat, the latest landlord gas safety record
If none are available, budget for a service soon after you move in. It is the easiest way to know what you have bought.
Timing a pre sale service
If you are about to list, book the service early. Google search data for London shows demand for boiler services in October running at about four times May and June. A spring or summer service fits well before most sales complete.
What if the service finds a fault?
If the engineer finds a fault, you have choices. You can fix it before listing, fix it before completion, or tell the buyer and reflect it in the price. Hiding a known fault is a bad idea, because the TA6 asks direct questions and answering falsely can cause legal problems later.
If the engineer finds something dangerous, they follow the gas industry unsafe situations procedure, which can mean turning the appliance off until it is repaired.
Who can do the service
Gas work in the UK must be done by a Gas Safe registered engineer. Ask to see the ID card and check the number on the Gas Safe Register.
Summary
You do not have to service your boiler to sell. But a recent record, the installation certificate and the warranty paperwork make the sale smoother and leave less room for awkward questions. Book an annual boiler service before you list.
Quick questions
What paperwork should I find for my boiler?
The Gas Safe building regulations compliance certificate from installation, the Benchmark checklist, service records and any warranty registration.
Will a buyer's survey test the boiler?
Usually not in detail. Surveyors note the boiler's age and condition and often advise the buyer to get it checked by a Gas Safe engineer.
Can I transfer the boiler warranty to the buyer?
Many maker guarantees stay with the boiler, but some need the new owner to register. Check the maker's terms.
Last updated 23 October 2026. Written for homes in London. Rules can change, so check the linked sources for the latest position.