Quick answer: ecobee lists the Smart Thermostat Essential at $139.99, the cheapest of the three models in its own comparison grid — Essential $139.99, Enhanced $199.99, Premium $259.99. You get a 2.8-inch 240 x 320 touchscreen, temperature and humidity sensing, Wi-Fi 6 on 2.4 GHz only, and a 3-year warranty. What you do not get in the box is the Power Extender Kit ($24.99) or the Trim Kit ($14.99) — ecobee includes both with the Enhanced. So in a home with no C wire and a marked-up wall, the Essential reaches $179.97 before it matches what the $199.99 Enhanced ships with. Buy the Essential if you have a C wire and a single-stage system; otherwise the extra $20.02 is the easier call.
Start with what ecobee actually publishes, because the side-by-side is sitting on its own site. Its thermostats page carries a comparison grid with three models priced in the header row — Premium $259.99, Enhanced $199.99, Essential $139.99 — marking each feature present or absent per tier. Each product page also carries a “View detailed specs” table with dimensions, terminals, radios, power draw and box contents.
Everything below comes from those pages and the official Smart Thermostat ESSENTIAL wiring guide PDF. Nobody at TheHomePicker has installed this unit — every number here is ecobee’s.
The Essential’s spec sheet
From ecobee’s “View detailed specs” table for this model:
- Price: $139.99 direct, with “Free standard shipping and returns”. (On Amazon the price is set separately and moves.)
- Display: “2.8 inch full-color LCD touchscreen”, “240 x 320 pixel display”.
- Size: 92mm (3.62in) high and wide, 23mm (0.91in) deep.
- Onboard sensors: Temperature and Humidity. That is the whole list.
- Radios: “Wi-Fi 6 @ 2.4 GHz” — no 5 GHz band — plus “Bluetooth BLE 5.4” and a “Sub-GHz radio”. Bandwidth “5MB/month”.
- Power: “Less than 3 VA”, supplied by “Wired 24VAC through terminals C and R”.
- Setpoint range: “45° to 120°F (7° to 49°C)”, sensitivity “+/− 1°F”.
- In the box: “Smart Thermostat Essential / Backplate / Quick start guide / Wire labels / Screws and drywall plugs” — then the decisive line: “Optional for installation: Smart Thermostat Essential Trim Kit, Power Extender Kit”.
- Warranty and returns: three years, though the same page words it three ways — “3-year extended warranty” in the spec table, “3-year manufacturer’s warranty” in the body, “3-year limited warranty” in the shop-direct block near the foot. “Return within 30 days for full refund”.
One line there beats the step-up models. The Essential’s setpoint runs to 120°F; the Enhanced and Premium spec tables both stop at 92°F. For a shop or a garage that needs a high heat setpoint, the cheapest of the three is the one that goes there.
Essential vs Enhanced vs Premium: what $60 and $120 actually buy
Every cell below is published by ecobee, on its own US pages.
| Smart Thermostat Essential | Smart Thermostat Enhanced | Smart Thermostat Premium | |
|---|---|---|---|
| ecobee price | $139.99 | $199.99 | $259.99 |
| Display | 2.8 inch, 240 x 320 pixel | 4 in., 540 x 540 pixel | 4 in., 540 x 540 pixel |
| Thermostat size | 92mm (3.62in) square, 23mm (0.91in) deep | 103.89 mm (4.09 in.) square, 23.88 mm (0.94 in.) deep | 103.89 mm (4.09 in.) square, 25.9 mm (1.02 in.) deep |
| Onboard sensors | Temperature, Humidity | Temperature, Humidity, Occupancy (Radar), Proximity (Radar) | Temperature, Humidity, Occupancy (Radar), Proximity (Radar) |
| HVAC compatibility | Conventional (2H/1C and 1H/2C), Heat pump (2H/1C) | Conventional (2H/2C), heat pumps (2H/2C + 1 stage AUX heat), boilers, PTACs or fan coil units up to 3 fan speeds | Conventional (2H/2C), heat pumps (2H/2C + 2 stage AUX heat), boilers, PTACs or fan coil units up to 3 fan speeds |
| Wire terminals | C, R, G/PEK, Y1, OB*, W1 (6) | R, G, Y1, Y2, W2/OB, PEK+, C, W1 (8) | Rc, G, Y1, Y2, OB, PEK+, C, Rh, W1, W2, ACC-, ACC+ (12) |
| Wi-Fi | Wi-Fi 6 @ 2.4 GHz (no 5 GHz) | Dual-band: 802.11 b/g/n @ 2.4GHz, 802.11 a/n/ac @ 5GHz | Dual-band: 802.11 b/g/n @ 2.4GHz, 802.11 a/n/ac @ 5GHz |
| Bandwidth | 5MB/month | 15-20 MB/month | 15-20 MB/month |
| “Works with” (spec table) | Google Assistant, Apple HomeKit, Amazon Alexa | Apple HomeKit, Amazon Alexa, Samsung SmartThings, IFTTT, and more | Apple HomeKit, Amazon Alexa, Samsung SmartThings, IFTTT, and more |
| Setpoint range | 45° to 120°F (7° to 49°C) | 45° to 92°F (7° to 33°C) | 45° to 92°F (7° to 33°C) |
| Power Extender Kit in the box | No — $24.99 separately | Yes | Yes |
| Trim plate in the box | No — Trim Kit $14.99 separately | Yes | Yes |
| SmartSensor in the box | No | No | Yes — “SmartSensor with detachable stand and adhesive wall-mount” |
| ecobee’s savings claim | Up to 23% | Up to 26% | Up to 26% |
Now the arithmetic the grid hides. ecobee prices the Power Extender Kit at $24.99, and the accessory card states the tier rule outright: “(Included with all models except Smart Thermostat Essential and Smart Thermostat Lite.)” The Trim Kit is $14.99. For a home with no C wire and a marked wall:
- $139.99 Essential + $24.99 Power Extender Kit + $14.99 Trim Kit = $179.97
- $199.99 Enhanced, which ships with “Power Extender Kit (PEK)” and “Trim plate” in the box
A $20.02 gap — and for it the Enhanced adds a 4-inch 540 x 540 screen, a radar occupancy sensor, dual-band Wi-Fi, full 2H/2C staging, and two more terminals. The Essential wins on price only when the C wire is already there and the wall needs no covering. Then it wins by $60.
The trim plate matters more than it looks: the Essential is 92mm square against the Enhanced’s 103.89 mm, so it is likeliest to leave an old outline showing — and of the three, the only one with no plate in the box.
Will it work with your HVAC system?
The staging limit, stated exactly
ecobee gives the rule in one sentence: “Smart Thermostat Essential also supports HVAC systems with 2 cooling stages plus 1 heating stage, or 2 heating stages plus 1 cooling stage, but not both.” The spec table says it in shorthand across Gas, Oil, Electric and Forced air. Beyond that, ecobee’s own advice: “For multistage heating and cooling setups, consider Smart Thermostat Premium.”
Heat pumps with auxiliary heat: supported, one stage
Entry-tier thermostats are assumed to fall over here. This one does not. ecobee’s official Essential wiring guide includes a diagram headed “HEAT PUMP (AIR OR GEOTHERMAL) WITH AUXILIARY HEAT”, and its compatible-systems block reads: “Heat pumps: Air, Water, and Geothermal with 1 stage of AUX heat.” It carries the aux settings — “Aux Heat Max Outdoor Temperature” (default 50°F), “Aux Min On Time” (5 minutes), “Compressor To Aux Temperature Delta” — and notes that “Heat pumps use an internet-based weather feed and do not require outdoor temp sensor and/or a dual-fuel kit.” One aux stage is the ceiling; two is a Premium feature.
No C wire: a $24.99 kit, and two exclusions
The Essential is hardwired, full stop: “Smart Thermostat Essential is hardwired, so you’ll never have to worry about losing control of your thermostat”, powered by “Wired 24VAC through terminals C and R”. There is no battery option. ecobee’s answer is the Power Extender Kit — “No C wire, no problem. Get the Power Extender Kit (sold separately).”
Two limits from the wiring guide are worth reading before you order: “The PEK is not compatible with dual transformer or fan coil units” (its summary block adds communicating units), and the boxed warning — “Do not connect it to line (high) voltage or millivolt systems. Limit 2A maximum current per terminal.” ecobee says to run your system through its Thermostat Compatibility Checker before adding a PEK to the cart. On install time ecobee publishes two figures on one page: “about 45 minutes” in the text, and a walkthrough noting approximately 30-60 minutes.
Free software, optional subscription, and which sensors work
The subscription answer is published, and it is good news. eco+ is free and built in — “Smart Thermostat Essential has built-in eco+, a free software” — and ecobee lists three eco+ features for this model: Adjust for Humidity, Time of Use (“Preheats or precools your home when energy is less expensive”), and the one with money attached, “Earn up to $125 from your utility provider with Community Energy Savings.”
Also documented for the Essential: Home Energy Reports, Vacation Mode, Pre-heating/Pre-cooling, AC Overcool to Dehumidify, Fan Dissipation, and reminders defaulting to Furnace Filter “Enabled, 3 months”. The only paid layer ecobee names is ecobee Smart Security, and it is optional: “plans starting as low as $5/mo ($7/mo in Canada)”, with “a 1-month free trial, no contracts, cancel anytime”.
On remote sensors: yes, with one named exception. The Essential page has a section headed “Works with SmartSensor” — “Pair with ecobee SmartSensor for balanced comfort” — and footnote 2 names what does not: “Smart Thermostat Essential is not compatible with ecobee Room Sensor™, our first-generation remote thermostat sensor.”
The honest part: what is missing, and what only looks missing
- The radar sensor — and what its absence does not cost you. ecobee’s comparison grid marks “Built-in radar occupancy sensor” present on Premium and Enhanced, absent on the Essential. That is the hardware gap. The eco+ occupancy features themselves are not walled off: the grid’s footnote 8 states they “work with Smart Thermostat Premium and Smart Thermostat Enhanced out of the box”, and that “Smart Thermostat Essential owners can take advantage of eco+ occupancy features by pairing their smart thermostat with an ecobee SmartSensor (sold separately).” ecobee’s eco+ page says the same of Schedule Assistant, which needs a built-in occupancy sensor “or paired sensor (SmartSensor or Room Sensor)” — here, a SmartSensor, since ecobee rules out the first-generation Room Sensor.
- A fourth model we could not price. The Essential page names a “Smart Thermostat Lite” twice, including in the PEK line above, but we could retrieve no price or spec table for it. Everything here compares the three models ecobee’s own grid compares.
- Product weight and maximum SmartSensor count: not published for this model.
- Voice hardware. Alexa Built-in appears only on the Premium page. The Essential’s spec table lists “Google Assistant, Apple HomeKit, Amazon Alexa” — control through those platforms, not a mic in the thermostat.
- The Amazon price. Amazon’s listing for this ASIN would not load for us, so we quote no number from it.
One claim deserves its own footnote. ecobee’s headline is “Reduce energy bills by up to US$250/CA$327 per year”, and its own footnote shows the working: “Based on an internal analysis conducted in April, 2021, select ecobee customers in North America saved up to 23% on their heating and cooling costs”, taking average energy costs of “$1,091 USD/$1,490.52 CAD” times 23%. That is a five-year-old manufacturer self-study, not an independent result — and its own arithmetic lands at “up to $251/$342 (USD/CAD) per year”, not the $250/$327 in the headline.
Which ecobee should you actually buy?
Buy the Essential ($139.99) if you have a C wire and a simple system
One furnace and one AC, or a heat pump with a single aux stage, a C wire already at the wall, no marks to cover. You pay $139.99, skip $39.98 of accessories, and what you give up — bigger screen, radar occupancy, 5 GHz Wi-Fi, a second cooling stage — you were not going to use. You still get app control, HomeKit, Google Assistant and Alexa, free eco+, a 3-year warranty, a 30-day return, and the only setpoint of the three reaching 120°F. Add a SmartSensor later and the eco+ occupancy features come with it.
Buy the Enhanced ($199.99) if you have no C wire
The Smart Thermostat Enhanced ships with the Power Extender Kit and trim plate in the box, so the no-C-wire install that costs $179.97 on the Essential costs $199.99 here — and that $20.02 also buys the 4-inch 540 x 540 display, the radar occupancy sensor behind Smart Home & Away, dual-band Wi-Fi, 2H/2C staging, and SmartThings and IFTTT. ecobee’s line for it: “Comes with everything you need for an easy self-install.”
Buy the Premium ($259.99) if your system is genuinely multi-stage
The Smart Thermostat Premium is the only one handling “heat pumps (2H/2C + 2 stage AUX heat)” and a two-wire accessory such as a humidifier, with 12 terminals to the Essential’s six. It ships with a SmartSensor, adds an indoor air quality monitor and Alexa Built-in, and is the model ecobee itself points multistage owners toward.
Add the $24.99 Power Extender Kit before the old thermostat comes off the wall
If you are not certain there is a C wire behind the plate, order the Power Extender Kit with the thermostat — “A cost-effective and efficient solution for homes without a C or common wire.” The alternative is a dead thermostat until it ships. Confirm first that you are not on a dual transformer or fan coil unit.
The verdict
ecobee documented this one properly, so the question is not whether it is any good — it is whether $139.99 is what you will actually pay. In a house with a C wire and a single-stage system, it is: same app, same free eco+, same 3-year warranty, same 30-day return, $60 less than the next model up.
In a house without a C wire, it is not. The $24.99 PEK and $14.99 Trim Kit put you at $179.97 for the smallest screen, no radar occupancy and 2.4 GHz-only Wi-Fi, while $199.99 buys the Enhanced with both included and every one of those specs improved. That is the one case where the cheapest model is the wrong buy.
ecobee Smart Thermostat Essential FAQ
Does the Essential need a C wire?
Yes, or the $24.99 Power Extender Kit. ecobee lists the powering method as “Wired 24VAC through terminals C and R” — there is no battery option. Homes without a common wire “can still support the Smart Thermostat Essential by using the ecobee Power Extender Kit, which is sold separately.” The PEK will not work on dual transformer or fan coil units.
Does it work with ecobee SmartSensor?
Yes — the Essential page has a “Works with SmartSensor” section, sensors sold separately, and pairing one is also how ecobee says Essential owners get the eco+ occupancy features. The one published exception is the old model: “Smart Thermostat Essential is not compatible with ecobee Room Sensor™, our first-generation remote thermostat sensor.” No maximum sensor count is published for this tier.
Will it run a heat pump with auxiliary heat?
Yes, with one aux stage. The official Essential wiring guide diagrams “HEAT PUMP (AIR OR GEOTHERMAL) WITH AUXILIARY HEAT” and states “Heat pumps: Air, Water, and Geothermal with 1 stage of AUX heat”. The ceiling is staging: “2 cooling stages plus 1 heating stage, or 2 heating stages plus 1 cooling stage, but not both.”
Is there a subscription?
One, and it is optional. ecobee lists eco+ as “a free software” built in, covering Time of Use, Adjust for Humidity and Community Energy Savings. The one paid layer ecobee names is ecobee Smart Security, “plans starting as low as $5/mo ($7/mo in Canada)”, with a one-month free trial.
What is the real difference between the Essential and the Enhanced?
$60, and six things on the spec sheet: a 4 in. 540 x 540 display instead of 2.8 in. 240 x 320; radar occupancy and proximity sensors; dual-band Wi-Fi instead of 2.4 GHz only; 2H/2C plus one aux stage instead of 2H/1C; eight terminals instead of six; and the PEK and trim plate in the box rather than $24.99 and $14.99 extra.
Pricing note: all prices here are ecobee’s own published US prices, read from ecobee.com on September 18, 2026. Amazon’s price is set separately and changes.
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