Garden Last updated · owner ratings verified July 2026
Affiliate Disclosure
Some links on this page are affiliate links. As an Amazon Associate, we earn from qualifying purchases — at no extra cost to you. We do not buy, test, or physically handle the products we cover; our rankings come from aggregated owner reviews, ratings and expert consensus. Commissions never change our verdicts. How we rank · full disclosure.
Side by side
| Our pick Google Google Nest Learning Thermostat Best overall $200-250 Check price | Google Google Nest Thermostat Cheaper Nest $110-140 Check price | Amazon Amazon Smart Thermostat Best value $60-85 Check price | Amazon Amazon Smart Plug For window AC $15-25 Check price | |
|---|---|---|---|---|
| What owners rate it | ||||
| Owner rating | 4.4 / 5 (23,817) | 4.2 / 5 (29,183) | 4 / 5 (25,235) | 4.7 / 5 (571,209) |
| Specifications | ||||
| What it controls | Replaces the wall thermostat | Replaces the wall thermostat | Replaces the wall thermostat | Switches power to a plug-in AC |
| Install requirement | DIY on most low-voltage systems; C-wire helps | DIY; C-wire required more often than on the Learning model | DIY, but a C-wire is required | Plug in, no wiring |
| Scheduling | Learns automatically plus manual schedules | Manual schedule plus Savings Finder suggestions | App schedules plus Alexa Hunches | Alexa routines and schedules |
| Room sensors | Supports remote room sensors | No remote sensor support | No remote sensor support | None |
| Energy features | Eco temperature, Home and Away, Energy History | Eco temperature, Home and Away, Energy History | Away mode, schedule setback, Energy Star certified | On and off scheduling only |
| Voice ecosystem | Google Home; also works with Alexa | Google Home; also works with Alexa | Alexa only for full control | Alexa |
| Best-fit AC type | Central AC and heat pumps | Central AC and heat pumps | Central AC and heat pumps | Window and portable AC units |
| Who it suits | ||||
| Best for | A central AC household that will never remember to change the setpoint | Nest scheduling and app control without the learning premium | An Alexa household that wants a scheduled setback for the least money | A window or portable AC, where no thermostat can help you |
Ratings are aggregated Amazon owner ratings, not our own testing. Figures verified July 2026.
Pros and cons
Google Nest Learning Thermostat
- Learns the schedule from how you actually adjust it, so the setback happens whether or not anyone remembers
- Works with Nest Temperature Sensors, which fixes the classic problem of one hot bedroom driving the whole house
- Owners consistently report the Home and Away detection is what produced their actual bill drop
- Most expensive option here by a wide margin
- Some older or high-voltage systems need a C-wire or a Nest Power Connector
- The learning phase takes a week or two, and owners who fight it end up scheduling manually anyway
Google Nest Thermostat
- Roughly half the price of the Learning model with the same app and the same Eco setpoints
- Savings Finder suggests schedule tweaks, which owners find more useful than the marketing implies
- Mirror finish disappears on a wall better than any thermostat here
- Does not learn; you set the schedule and it keeps it
- Does not support Nest Temperature Sensors, so hot-room balancing is out
- More systems need a C-wire on this model than on the Learning Thermostat
Amazon Smart Thermostat
- Cheapest smart thermostat from a major brand, often by half
- Energy Star certified and built on Honeywell Home thermostat technology
- Alexa Hunches will nudge or adjust it automatically once the household routine is established
- Requires a C-wire, and owners without one report this is where the project stalls
- No remote room sensors, no learning, and no on-device schedule editing worth using
- Lowest owner rating of the thermostats here, with setup and compatibility the common theme
Amazon Smart Plug
- The only option here that works with a window unit, which is how a great many US homes are cooled
- Enormous owner-review base and one of the highest ratings of any smart home device
- Routines can shut the unit off when everyone leaves and start it an hour before anyone gets home
- Switches power, it does not sense temperature, so it cannot hold a setpoint
- Only works if the AC unit resumes its previous mode after a power interruption
- Alexa ecosystem only in practice
Decision factors
What you actually pay
The purchase spread here is unusually wide for products that do the same core job. The Amazon Smart Thermostat typically lands around a third of the Nest Learning Thermostat, and the two sit within a couple of degrees of the same result if — and this is the whole condition — you keep the schedule accurate yourself.
The number that actually pays for any of them is your cooling bill. The Department of Energy estimates savings of up to 10 percent a year on heating and cooling from setting the thermostat back 7 to 10 degrees for eight hours a day, and Energy Star’s recommended summer setpoint is 78F while you are home. Google publishes an independent-study figure of roughly 15 percent cooling savings for the Nest thermostats. Against a typical summer cooling bill, the Amazon unit pays for itself inside a season and the Nest Learning inside two.
The hidden cost is the C-wire. Both Amazon and the cheaper Nest expect a common wire at the thermostat, and older homes frequently do not have one. Adding one means either running new cable or fitting an adapter, and if you pay an electrician for that it can cost more than the thermostat did. The Nest Learning Thermostat is the most forgiving on this point, which is part of what the premium buys.
If you cool with window units, none of the thermostat arithmetic applies. A smart plug plus a disciplined routine is the entire product category, it costs under $25, and the saving comes from not cooling an empty apartment rather than from any clever algorithm.
Which one fits you
- Central AC, and nobody in the house adjusts anything Google Nest Learning Thermostat Learning plus Home and Away detection is what turns a good setpoint into an actual bill reduction.
- One bedroom is always too hot Google Nest Learning Thermostat It is the only device here that supports remote temperature sensors, which is the real fix for an unbalanced house.
- Alexa household on a budget Amazon Smart Thermostat Energy Star certified, cheapest of the majors, and Hunches handle the setback once your routine is established. Check for a C-wire first.
- Window or portable AC Amazon Smart Plug A thermostat cannot help you. Scheduling the unit off while the apartment is empty is where the whole saving lives.
If neither is right
- ecobee Smart Thermostat Premium Ships with a room sensor in the box rather than as an accessory, has Alexa and Siri built in, and adds an air quality monitor. The most capable thermostat of the group and priced accordingly — worth it if your house has hot and cold rooms rather than a single problem zone.
- Sensi Smart Thermostat The pragmatic middle. Energy Star certified, works with both Alexa and Google, and it is the friendliest of the group toward homes without a C-wire on common system types. Fewer features, fewer install headaches.
- Sensibo Air For ductless mini-splits and any AC with an infrared remote. It learns the remote codes and adds scheduling, geofencing and a real setpoint to units that no wall thermostat can control. The right answer for a mini-split house.
Which should you actually buy?
If you have central AC and want the biggest bill reduction with the least discipline, buy the Google Nest Learning Thermostat. If you have central AC, a C-wire and an Alexa household, buy the Amazon Smart Thermostat and put the difference toward a service on your system. If you cool with a window unit, ignore the thermostats entirely and buy an Amazon Smart Plug. That last case is not a consolation prize — a great many US homes are cooled that way, and a plug plus a routine is the whole solution.
What is the right AC setpoint anyway?
Energy Star’s published guidance is 78F when you are home and awake in summer, stepping up while you are out and overnight. The Department of Energy’s figure for the saving is up to 10 percent a year from setting back 7 to 10 degrees for eight hours a day. Neither number is a brand claim; both are the baseline every thermostat on this page is trying to help you hit.
The point most people miss is where the saving comes from. It is not from being uncomfortable while you are home — it is from not cooling an empty house. Cooling load scales with the difference between inside and outside temperature, so the hours nobody is there are the hours worth attacking. That is why the technology that matters is the automation, not the display. Our full guide to the best AC temperature to save money works through the numbers by climate.
Does the Nest learning feature earn its premium?
On the owner-review record, yes, but for an unglamorous reason: it removes the human. The recurring theme in reviews of every smart thermostat is that the savings evaporate when someone overrides the schedule and forgets to put it back. The Learning Thermostat handles that by building the schedule from your actual behavior and using phone location to drop into Eco mode when the house empties.
It is also the only device on this page that supports remote temperature sensors. If your complaint is that the upstairs bedroom is unbearable while the hallway thermostat reads a comfortable 74F, no amount of scheduling fixes that — you need the system to control to the room that matters. That single capability is worth more than every other difference between these products for a house with an unbalanced second floor.
Where does the Amazon thermostat genuinely win?
Price, and the fact that it is Energy Star certified while costing a third of a Nest Learning. It is built on Honeywell Home thermostat technology rather than being an Amazon design from scratch, and the fundamentals — accurate sensing, reliable relay control, a working schedule — are sound. In an Alexa household it also inherits Hunches, which will notice that nobody is home and adjust without being asked.
Its weaknesses are specific rather than general. It requires a C-wire, which excludes a slice of older homes. It has no room sensors. Its on-device controls are minimal, so everything meaningful happens in the app. And its owner rating is the lowest of the three thermostats here, with setup and system compatibility the recurring theme rather than day-to-day performance. Check your wiring before you buy, and it is a bargain; skip that step and it is a return.
Does the voice ecosystem actually matter?
More than people expect, because the useful features live in the app and the routines. The Amazon thermostat is effectively an Alexa device; you can see it elsewhere, but Hunches and routines are the reason to own it. The Nest thermostats are Google Home devices that also respond to Alexa for basic commands. Whichever ecosystem your speakers, cameras and lights already sit in should probably decide this, because a thermostat that participates in a leaving-the-house routine saves more than one that sits on its own schedule.
If you are ecosystem-agnostic, that is an argument for looking outside both brands — the alternatives below include options that speak to Alexa, Google and Siri equally, and our best smart thermostat rankings cover the whole field.
Can you install these yourself?
Usually. A standard low-voltage central system with clearly labeled wires is a 30 to 45 minute job with a screwdriver and a phone camera to photograph the old wiring before you touch it. The complications are always the same two: no C-wire, and high-voltage or proprietary systems that no consumer thermostat supports. Neither is discovered from the product page, both are discovered by taking the old thermostat off the wall.
Our walkthrough on installing a smart thermostat yourself covers the wiring check, and how smart thermostats save money explains which features are doing the work.
The call
Google Nest Learning Thermostat is the better product and the bigger saver, because it automates the behavior that produces the saving and it can control to the room that is actually uncomfortable. The Amazon Smart Thermostat is the better value by a wide margin and gets you most of the way there in an Alexa house with a C-wire. And if your AC lives in a window, the Amazon Smart Plug is not a compromise — it is the correct product.
Everything here is ranked from aggregated Amazon owner ratings and published expert consensus rather than first-hand trials; see how we rank. For the arithmetic on payback, read how much a smart thermostat saves per year.