Ecobee sells two different smart thermostats, both of which offer different features at different prices. If you’re in the market for a smart thermostat and have narrowed it down to Ecobee, here are some things you should know about the Ecobee4 and the Ecobee3 Lite before you make an official purchase.

RELATED: How to Get the Most Out of Your Ecobee Smart Thermostat

Ecobee’s previous flagship smart thermostat was the Ecobee3, but that was eventually replaced by the newer Ecobee4. However, if you don’t quite need the best model available and are eying the Ecobee3 Lite, here are the differences between the two models.

Ecobee4 Has Alexa Built In

Interestingly enough, the Ecobee4 is nearly identical to the older Ecobee3, save for the addition of Alexa capabilities, which essentially turns the Ecobee4 into a full-blown Echo Dot of sorts.

The Ecobee4 comes with a speaker and far-field voice recognition microphones with Alexa running the show, turning the thermostat into a 2-in-1 device. So if you’ve ever wanted an Echo in your living room, you can now kill two birds with one stone.

However, several things aren’t supported by Alexa on the Ecobee4, like Spotify, or calling, messaging, and Drop In, which we assume is a limitation with third-party Alexa devices.

Ecobee3 Lite Doesn’t Come with a Room Sensor

RELATED: How to Manually Select Which Ecobee Sensor to Use

The Ecobee line of smart thermostats has become so popular largely due to remote sensors that you can place around your house. So if you wanted the heating or cooling to focus on the bedroom, you can tell the Ecobee to do just that. However, while the Ecobee3 Lite now supports remote sensors (it didn’t use to), it doesn’t come with one in the box.

If you buy the Ecobee3 Lite, you’ll need to buy the remote sensor separately, and you can only get them in a two-pack for $79, although you can buy a bundle that comes with the thermostat and two sensors for a bit cheaper. You may be also be able to find used ones for even cheaper.

Both Support Major Smarthome Platforms

If integration with other smarthome devices is a feature you want in your smart thermostat, then you’ll be glad to hear that both the Ecobee4 and Ecobee3 Lite work with most major smarthome platforms.

The two thermostats work with Alexa, Apple’s HomeKit, IFTTT, SmartThings, Wink, and more. Unfortunately, though, Google Assistant doesn’t support either Ecobee thermostats currently.

Ecobee3 Lite Is Slightly Smaller & Thinner

This probably isn’t a huge deal for most users, but if it is for you, then you may want to know that the Ecobee3 Lite is actually a tad smaller and thinner than the Ecobee4.

The Ecobee3 Lite is almost a half-inch smaller in length and width, as well as around an 1/8-inch thinner. Again, that’s not a whole lot, and we’re guessing the Ecobee4 is bigger because of the innards required to provide Echo-like abilities.

Ecobee4 Comes with More Wire Terminals

If you have a newer, complex HVAC system, it might be important to know that the Ecobee3 Lite doesn’t include as many wire terminals as the Ecobee4.

This probably won’t make a huge difference for most people, as the Ecobee3 still has 10 terminals compared to the Ecobee4’s 12 terminals, and the only terminals missing on the Ecobee3 Lite are “ACC -” and “ACC +”, which are usually required if you have a dehumidifier, humidifier, or ventilator as part of your HVAC system.

Ecobee3 Lite Is Much Cheaper

Cost is obviously one of the biggest factors when it comes to deciding which smart thermostat to buy, so I’ve saved the best for last. The Ecobee3 Lite is a whopping $80 cheaper than the Ecobee4.

The Ecobee4 is priced at $249 (the same price as its predecessor), but the Ecobee3 Lite only costs $169. Again, though, it doesn’t include a remote sensor, so you’ll still have to pay a little more if that’s something you really want, but you’ll likely still come out ahead of the Ecobee4 price-wise.