Is it a legal requirement to have a thermostat on a boiler?

In short: not always... but in many cases, yes.

In the UK, there is no law that says every boiler must have a thermostat. However, building regulations do require effective temperature control for most heating systems, and in practice, this usually means a thermostat.

New boiler installations and replacements

If you’re installing a new boiler or replacing an existing one, UK Building Regulations (Part L) require suitable heating controls. A thermostat is typically required to meet this standard.

Existing boilers

If a boiler was installed years ago, there is no legal requirement to add a thermostat just because regulations have changed.
That said, if the system is upgraded or altered, adding proper temperature control may be expected.

Landlords and rental properties

There is no single law stating landlords must install a thermostat. However, landlords are legally responsible for:
- Providing safe, working heating
- Meeting energy efficiency standards
- Allowing reasonable control of heating

For this reason, thermostats are widely used in rental and HMO properties, even when not strictly named as a legal requirement.
A simple thermostat is one of the easiest ways to stay compliant and avoid wasted energy.

At TIME:O:STAT, we design straightforward, reliable thermostats that give clear temperature control without unnecessary complexity.