Upgrading to a smart thermostat can save you 15 to 31% on your heating bill without sacrificing comfort. But with so many options available, it can be hard to decide. This comparison focuses on the 3 most popular models for gas and oil boilers.

Comparison table

Feature	Tado V3+	Netatmo	Honeywell T6
Approx. price	~£130	~£110	~£65
Subscription	Optional (~£3/mo)	None	None
Geo-tracking	Yes	No	No
Open window detection	Yes	Yes	No
OpenTherm compatible	Yes	Yes	Yes
Open API / home automation	Limited	Yes	No
Estimated savings	~31%	~20%	~15%

Tado Smart Thermostat V3+

The smartest option. Tado uses your smartphone's location to anticipate your arrival home and heats only when needed. It also detects open windows and cuts heating automatically.

• Pros: maximum savings, polished app, detailed energy reports
• Cons: Auto-Assist features require a subscription, higher upfront cost
• Best for: those who want maximum automation and the best savings

→ View Tado V3+ on Amazon.co.uk

Netatmo Smart Thermostat

Best subscription-free option. Netatmo offers a solid connected thermostat with no monthly fees. Its open API makes it ideal for home automation enthusiasts (Apple HomeKit, Google Home, Home Assistant).

• Pros: no subscription, HomeKit & Google Home compatible, open API
• Cons: no native geo-tracking, less intuitive interface
• Best for: home automation fans, Apple HomeKit users

→ View Netatmo on Amazon.co.uk

Honeywell Home T6

Most affordable option. The Honeywell T6 is a simple, reliable connected programmable thermostat — perfect for replacing an old thermostat without breaking the bank.

• Pros: affordable price, easy installation, reliable long-term
• Cons: no geo-tracking, basic app, fewer automatic savings
• Best for: those who just want a modern programmable thermostat at a reasonable price

→ View Honeywell Home T6 on Amazon.co.uk

Our verdict

For maximum savings: choose Tado V3+. To avoid subscriptions and use home automation: go for Netatmo. For a tight budget with essential features: Honeywell T6 does the job very well.

Pair any of these with our programming calculator to fine-tune your heating schedule.

Frequently asked questions

Does Tado require a subscription?
Basic geo-tracking is free. Advanced Auto-Assist features cost ~£2.99/month or £22.99/year.

Are these thermostats compatible with my boiler?
Tado, Netatmo and Honeywell T6 are compatible with the vast majority of gas and oil boilers. Check OpenTherm compatibility on the manufacturer's site.

Which smart thermostat saves the most?
Tado claims up to 31% savings through geo-tracking. Netatmo and Honeywell offer 15–20%.