How long Baxi guarantees last, the conditions you must meet to keep yours valid, what it covers, and how a manufacturer warranty differs from ongoing boiler cover.
Home›Blog›Baxi boiler warranty
If you've had a new Baxi boiler fitted, the manufacturer's guarantee is one of the most valuable things that came with it — but only if you keep it valid. Baxi (part of the BDR Thermea group, alongside brands such as Potterton and Heatrae Sadia) offers warranties that range widely depending on the model and how it was registered. Below we explain the typical lengths, the conditions attached, what's covered, how to make a claim, and how a warranty differs from the boiler cover policies many homeowners also take out.
There is no single answer, because the length depends on the model and, crucially, on whether it was registered within the stated window. Across Baxi's current combi, system and heat-only ranges, guarantees commonly fall somewhere between 2 and 10 years. Entry-level models tend to sit at the lower end; flagship combis and bundles bought with a filter or installed by an accredited installer often reach the higher figure.
A few points worth understanding:
Always confirm your own model's terms. The only reliable source is the guarantee paperwork supplied with your boiler, or your registration confirmation. Treat the ranges here as a general guide, not a promise for your specific unit.
A manufacturer's guarantee is conditional. With Baxi, three requirements come up again and again, and falling short of any of them is the most common reason a claim is refused.
Baxi normally asks you to register the boiler within a set period after installation — often around 30 days. Registration is free and is usually done online or by phone. Without it, you may default to a shorter standard guarantee, or have no extended cover at all. Your installer sometimes registers on your behalf, but don't assume it has been done — check.
To keep the guarantee live, the boiler must be serviced every year by a Gas Safe registered engineer. The service must be carried out on time (typically within a window around each anniversary of installation) and recorded properly. Skipping a year — or letting it slip late — is enough to invalidate the remaining term on many policies. Keep your receipts and service records; you may be asked to produce them when you claim.
The Benchmark Checklist is the industry commissioning record that your installer should complete and sign at handover, then update at each annual service. A missing or blank Benchmark logbook is a frequent sticking point in warranty disputes, so make sure yours was filled in on day one and is kept with the boiler documents.
| Condition | Why it matters |
|---|---|
| Register in time | Unlocks the full advertised length rather than the shorter standard term |
| Annual Gas Safe service | Keeps the guarantee live year on year; missing one can void the rest |
| Benchmark logbook completed | Proves correct commissioning and ongoing servicing if you claim |
| Installed by a competent person | Faults caused by poor installation are typically excluded |
A manufacturer's guarantee is designed to cover defects in the boiler itself — faulty parts and manufacturing problems within the warranty period. If a covered component fails, Baxi arranges repair or replacement of that part, and the associated labour, under the guarantee terms.
What it generally does not cover:
This is exactly where many homeowners get caught out: the boiler is still "in warranty" on paper, but the claim is declined because a service was missed or the fault sits outside the boiler. It's worth reading our explainer on what boiler cover actually is to see where a warranty ends and a separate policy begins.
If you think your boiler has a covered fault, the broad process is:
Safety first. Never attempt DIY repairs on the gas valve, gas pipework, the flue, the sealed/pressurised circuit, the pressure relief valve or behind the boiler casing. These are gas-safety-critical and must only be touched by a Gas Safe registered engineer. If you smell gas or suspect carbon monoxide, leave the property and call the National Gas Emergency line on 0800 111 999.
People often use "warranty" and "boiler cover" interchangeably, but they're not the same thing.
The two can work together: your warranty handles boiler defects for the first few years, while a cover policy can fill the gaps (system faults, controls, an included service) and take over once the guarantee runs out. If you're weighing up whether to pay for a policy at all, our guide on whether boiler cover is worth it walks through the trade-offs, and you can line up plans side by side on our best boiler cover comparison.
Generally no — the warranty requires an annual service to stay valid, but you arrange and pay for that service yourself unless it's bundled into a separate cover plan. Always use a Gas Safe registered engineer and keep the record.
Missing or delaying the annual service can invalidate the remaining warranty, even if the boiler is otherwise still within its term. Check your specific guarantee wording, as the exact rules vary by policy.
Many Baxi guarantees can transfer to a new homeowner, sometimes for the remaining period, provided the servicing record is intact. Confirm the transfer process with Baxi, as terms differ by model and registration.
Contact Baxi with your boiler's serial number and installation address; if you registered, your details should be on file. The serial number is usually on a label on or inside the boiler casing or on the original Benchmark logbook.
No — it covers the boiler itself. Radiators, most controls and external pipework sit outside it. That's the gap a separate boiler cover policy is designed to address.
See how cover plans line up on price, callouts and what's included — and find one that complements your manufacturer warranty.
Compare boiler coverThis article is general information, not advice, and reflects indicative 2026 terms for a selected panel of providers rather than the whole market. Warranty lengths and conditions vary by model and registration — always confirm the exact terms for your own Baxi boiler with Baxi or your installer.