How much does a gas safety certificate cost in Northern Ireland?

The researched NI 2026 ranges: a standalone CP12 safety check, covering one boiler and up to two extra gas appliances such as a hob or a fire, runs £60 to £95. A CP12 combined with an annual boiler service in the same visit runs £110 to £170, and because the engineer is already at the appliance this combined visit is usually the better-value booking. Multi-property landlords booking five or more certificates together can typically negotiate £45 to £65 per certificate. Expect a premium of roughly a quarter for out-of-hours or weekend visits, and be aware that some national chains quote £150 or more for a single CP12 that a local Gas Safe engineer would price inside the standard range.

What moves the price within those ranges is mostly appliance count and access: every gas appliance in the property goes on the same certificate, so a house with a boiler, hob and fire is a bigger job than a flat with a single boiler. Only a Gas Safe registered engineer can legally inspect gas appliances and issue the certificate, and the register is free to check, so verify the engineer at gassaferegister.co.uk before booking and confirm how many appliances the quoted price covers.

One NI-specific check before you book anything: most homes here heat with oil, not gas. If your boiler is oil-fired, a CP12 is the wrong paperwork entirely, you need an OFTEC registered engineer and an annual oil service, which runs £90 to £160. And if you are a landlord, the certificate is a legal requirement every 12 months under the NI gas safety regulations, with a copy to tenants within 28 days of the check, so build the renewal into the tenancy calendar rather than the panic the week a tenancy starts.

If a quote you have been given sits outside these ranges, our free Quote Checker will tell you in a minute how it compares to the researched NI figures, and the full guide covers who can issue the certificate, what gets checked on the day, and the landlord rules in detail.