nobadbuys
Verified Aug 8 2026
Dossier Nº ST-26-2039
Query: Smart thermostat · Anyone · Under $250
12 independent sources
12 models tested · Bob Vila 5/5, all criteria
Confidence 93%

The answer — one pick, priced

Get the

Nest Learning 4th Gen

$249
Silver, bundled with the Nest Temperature Sensor (2nd gen) · $249 on Amazon, below the $280 list · no C-wire required, nothing extra to buy to install it
$1 under your budget

The one flagship that needs no C-wire at all — a perfect 5/5 from Bob Vila, Matter for Apple Home, and a Nest Temperature Sensor bundled into the $249.

Nest Learning 4th Gen
Nest Learning · 4th gen2.7-IN · NO C-WIRE

Fit ledger — need → measured evidence

OLD WIRING
No C-wire required — it is engineered to run on power-sharing, which makes it the safest pick for a 1960s-80s four-wire bundle. No $10-$30 adapter, no electrician.
CROSS-PLATFORM
Matter certified, so it joins Apple Home, Google Home and Home Assistant with no proprietary bridge — something no ecobee on this list does.
HANDS-OFF SCHEDULE
It learns your preferred temperatures within about a week and builds the schedule itself; Adaptive Eco uses outdoor temperature for setpoints while you are out.
WHAT $249 INCLUDES
The price is the bundle with a Nest Temperature Sensor (2nd gen); up to six are supported at ~$40 each — but they read temperature only, with no occupancy sensing.
BUY THE 4TH GEN
Google cut off 1st and 2nd generation Nest Learning Thermostats on 25 October 2025 — those units no longer connect to the Google Home or Nest apps. Do not buy a used one.
UNDER $250
$249 against a $280 list leaves exactly $1 of headroom, and it now undercuts the $260 Ecobee Premium — a reversal of the pricing this category had in July.

  The catch — co-equal billing, always

Google has form for switching thermostats off. First and second generation Nest Learning Thermostats stopped connecting to the app on 25 October 2025 and receive no further security updates. Nothing says the 4th gen is next, but a decade of service is not this brand's documented record — and Google Home Premium ($10/mo or $100/yr) is the tier the ecosystem keeps pushing, even though thermostat control stays free.

Dealbreaker? Runner-up №2 has no cloud and no vendor account at all ↓

  Every product has a catch. Verdicts that hide it are how bad buys happen.

Don't buy this if…

  • you need a basic programmable thermostat without Wi-Fi or smart features
  • you are looking for a smart home hub, not a thermostatSmart home hub verdict →
  • you have a ductless mini-split or window AC controlled only by an infrared remote, with no thermostat wiring at all

Wrong product for you is still a bad buy. These are the cases where we'd send you somewhere else.

Runners-up — if your needs differ

Adjacent verdicts — other needs, same method

Different budget, different household, different job — each of these is already researched, priced and verified. Take the one that matches your need.

Traps — this verdict avoids

Why the Nest Learning 4th Gen is right for you

It avoids every trap below — and for anyone, under $250, it is the pick because it delivers:

Old wiring Cross-platform Hands-off schedule What $249 includes Buy the 4th gen
Trap 01

The C-wire decides this, not the brand

Sensi Touch 2, Honeywell T9, Honeywell X2S and the Amazon Smart Thermostat all require a common wire outright — with no C-wire that means an add-a-wire adapter at $10-$30, or an HVAC call-out that can cost more than the thermostat. Both Google Nest models need none, every Ecobee ships a Power Extender Kit in the box, and the Honeywell X8S includes a free adapter via an in-box promo code. Photograph the terminal block behind your current thermostat before you order anything.

Trap 02

Line voltage is a different product class

If your heat is 120V or 240V electric baseboard, fan-forced or convector, none of the 24V picks here work at all — wiring one to line voltage is a fire and shock hazard, not merely unsupported. Mysa for Baseboards is the answer: up to 1900W at 120V or 3800W at 240V, at least four wires including a neutral or second live, and one unit per heater circuit, so a whole-home retrofit is a multi-unit purchase.

Trap 03

The sensors are the comfort, and they cost extra

A thermostat only measures the hallway it is screwed to. Balancing rooms means sensors, and most are sold separately: ecobee SmartSensor ~$80 per 2-pack (temperature plus occupancy), Google Nest Temperature Sensor ~$40 each (up to six, temperature only), Honeywell room sensors ~$40-45 each (up to 20 on the X8S, 200-foot range). Only the Ecobee Enhanced gets occupancy sensing with zero accessory spend, via built-in radar.

Provenance — 12 sources, dated

Winners are picked from the full research dossier at knowledgelib.io. Prices, stock and listings are re-verified monthly.

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Nest Learning 4th Gen$249 · See it on Amazon →