Consumers with manual thermostats can cut their energy bills by as much as 10 percent a year by switching to a programmable thermostat, according to the U.S. Department of Energy. When cold weather sets in, the thermostat can be set to automatically lower the temperature during sleep or during the day when no one's home. Cheapism.com's research into the best cheap thermostats found several reliable and easy-to-use programmable thermostats under $50. Smart thermostats that can be controlled remotely cost more upfront, but this roundup includes two strong picks for homeowners who want Wi-Fi connectivity without the bells and whistles that push prices well into the triple digits.
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The Honeywell RTH2300B1012 (starting at $23) is a 5-day/2-day programmable thermostat that allows one schedule for weekdays and another for weekends. This model gets high marks for trouble-free operation and simple controls. A straightforward permanent hold function lets users easily override preset temperatures, and reviewers also like the backlit screen for nighttime adjustments. Note that this model won't work with multi-stage heating and cooling systems.
Thorough, step-by-step instructions make installing the Honeywell RTH6350 (starting at $43) quick and seamless with most heating and cooling systems, including multi-stage heaters. Reviewers also appreciate the large, backlit screen and easy-to-press buttons on this 5-day/2-day thermostat. Users can adjust how much the temperature is allowed to fluctuate before triggering the heating or cooling system, although some would like to be able to program more than a 1-degree swing.
The Lux TX9100U (starting at $34) is about as cheap as it gets for a thermostat that lets users program each day individually, making it well worth a look for frugal consumers with variable schedules. Other notable features include a lockable, backlit screen, a quick-copy setting that allows faster programming, and an adjustable temperature swing that many reviewers credit with reducing wear and tear on their heating and cooling systems. Some say the controls have a learning curve, though.
For just few dollars more than the Lux TX9100U, the Lux TX9600TS (starting at $41) delivers a large, bright touchscreen that does away with all the up/down fiddling of standard programmable thermostats. Because it allows users to program each day individually, this thermostat is more versatile than many other budget models. Users also rave about the adjustable swing, which gives them more control over how often their heating and cooling systems kick on. The few qualms that pop up in reviews are minor things like a buzzing sound from the display.
Homeowners with electric baseboards, convectors, radiant ceilings, and fan-forced heaters have limited options, but one of the best is the 5-day/2-day Honeywell RLV4305A1000/E (starting at $45). Reviewers say this line-voltage thermostat helps maintain consistent temperatures and deliver less painful heating and cooling bills. They also say it's easy to install, program, and use, with a backlight for middle-of-the-night changes. Users with fan-forced heaters should pay close attention during setup and tweak their settings to head off constant system cycling, some reviewers say.
Consumers with space heaters and window air conditioners welcome the versatility of the Lux WIN100 (starting at $36), which adds 5-day/2-day programmability for those appliances wherever they may be -- a little-used spare room, a garage workshop, a chicken coop -- as long as there's an outlet. Like other Lux thermostats, the WIN100 has an adjustable swing and easy-to-use temperature override. Note that this model doesn't have a backlight, and some reviewers wish for a wider temperature range than 45 to 90 degrees.
Smart thermostats aren't cheap, but the Honeywell RTH6580WF (starting at $83) shows that they don't have to cost several hundred dollars, either. This thermostat includes a Wi-Fi connection for users who want to control their home's temperature remotely via an easy-to-use Apple iOS or Android app. It also features individually programmable days, a backlight, and customizable temperature-range alerts. Some users warn that this thermostat sometimes loses its Wi-Fi connection.
The Emerson Sensi (starting at $110) packs in a lot of features at a fraction of the cost of other smart thermostats. Users can connect to the thermostat remotely via a detailed, easy-to-use app, and the Sensi is compatible with Amazon Echo, which allows voice control, and the Wink smart-home hub. This backlit thermostat also doesn't require a C-wire, or common wire, for many installations, making it compatible with more heating and cooling systems. Some reviewers say the thermostat's onboard controls aren't quite as simple as the ones on the app, and some report the usual Wi-Fi connectivity issues.