Nest Learning Thermostat (4th Gen) vs. Honeywell T9: Nest is Better, But...

Naila Syifa

Updated October 2024

Nest Learning Thermostat (4th Gen) vs. Honeywell T9

If you're in the market for a smart thermostat, you've likely come across these two popular options. Nest Learning Thermostat (4th Gen) and Honeywell T9 Smart Thermostat are some premium models that offer advanced features and energy-saving capabilities, but which one is the better choice for your home?

On our list

#1 Design

#2 Features

#3 System Compatibility & Setup

Key Takeaways

Feature-wise, the Nest Learning Thermostat (4th Gen) is overall smarter, but the Honeywell T9 offers better multi-room control with its temperature and occupancy-detecting Smart Room Sensors. Nest Learning Thermostat (4th Gen) also has wider compatibility with complex HVAC systems, supporting humidifiers, dehumidifiers, and ventilation systems that the Honeywell T9 doesn't support.

Honeywell T9 suits larger homes needing room-by-room temp control, while Nest Learning Thermostat (4th Gen) is great for folks wanting automated energy savings and temp management.

	Nest Learning Thermostat (4th Gen)	Honeywell T9
Dimensions	3.9” x 3.9” x 1.1”	3.7” x 4.92” x 0.94”
Touchscreen	❌	✅
Built-In Humidity Sensor	✅	✅
Built-In Occupancy Sensor	✅	❌
Air Quality Monitoring	✅ Outdoor	❌
App Control	✅	✅
Auto-Schedule	✅	❌
Home & Away	✅	✅
Smart Home Integration	Alexa, Google Assistant, Apple HomeKit, SmartThings, Matter	Alexa, Google Assistant, Apple HomeKit, SmartThings
Additional Sensor	Temperature Sensor (up to 6)	Smart Room Sensor (up to 20)
C-Wire Required	❌	✅ Adapter Included
Hum/Dehum/Vent	✅	❌

Nest Learning Thermostat (4th Generation)

Intelligent Energy Saving & Comfort

✓ 2.7” Display with Dynamic Farsight
✓ Smart Schedule & Adaptive Eco
✓ Matter-Certified
✓ 12 Wiring Terminals

Buy on Amazon

Honeywell T9 Smart Thermostat

Thermostat for Larger Homes

✓ Touchscreen LCD
✓ Adaptive Recovery
✓ Active Rooms & Multi-Rooms Prioritization
✓ Up to 20 Smart Room Sensors

Buy on Amazon

Design

Nest Learning Thermostat (4th Gen)

Nest Learning Thermostat (4th Gen) boasts a modern, beautiful design with a borderless display and slim profile. The thermostat is circular with a 3.9" diameter and there are three metal finishes to choose from – Polished Silver, Polished Obsidian, and Polished Gold.

What I like about the Nest Learning Thermostat (4th Gen) is the home screen, which can be customized to display different information depending on our proximity to the device. For example, it can show a clock when we're far away and switch to display the temperature as we approach. This is possible thanks to the Dynamic Farsight feature, which uses built-in sensors to detect someone's presence and adjust the display accordingly.

Compared to Nest, the Honeywell T9 has a more basic, industrial design in a white, rectangular shape. However, the 1.8” x 2.8” display is a touchscreen LCD, unlike the Nest Learning Thermostat (4th Gen) which uses a rotating ring for temperature adjustment instead of a touch display.

Features

Honeywell T9

Both the Nest Learning Thermostat (4th Gen) and Honeywell T9 offer remote control from the app, a built-in humidity sensor, energy-saving away mode, and integration with smart home ecosystems like Alexa, Google Assistant, Apple HomeKit, and Samsung SmartThings.

What gives the Honeywell T9 a clear edge is the Smart Room Sensor it works with. The thermostat only comes with one sensor, but up to 20 sensors are supported for multi-room temperature monitoring and control. The sensor can sense temperature and occupancy, so the thermostat can be set to prioritize occupied rooms (or so-called "Active Rooms"). Otherwise, we can also manually select one or multiple rooms for prioritization.

While the Nest Learning Thermostat (4th Gen) also comes with a sensor, Nest Temperature Sensor (2nd Gen), it only detects room temperature and not occupancy. That means occupancy-based room prioritization is not supported. Only manual room selection is possible for prioritization. Furthermore, the thermostat can only handle 6 sensors, a far cry from the 20 sensors supported by the Honeywell T9.

Nest Learning Thermostat (4th Gen)

When it comes to learning capabilities, the Honeywell T9 is losing to the Nest. With Adaptive Recovery, Honeywell T9 can learn how long it takes to heat or cool your home and adjust accordingly to reach your desired temperature at the scheduled time, but that's all about it.

Nest Learning Thermostat (4th Gen) goes beyond that by learning your temperature preferences and daily routines to create an automated schedule. If you're away, the Adaptive Eco feature finds the right temperature to save energy while ensuring it can return to your preferred temperature quickly one hour after you return home.

Nest Learning Thermostat (4th Gen) can also leverage outdoor weather and air quality data to optimize your indoor climate and energy usage. The Natural Heating/Cooling feature uses outdoor temperatures to reduce energy consumption when possible, while Smart Ventilation adjusts your ventilation system based on outdoor air quality.

On top of that, Nest Learning Thermostat (4th Gen) can identify potential HVAC issues and alert you before they become major problems, while Honeywell T9's alert system is limited to frost alerts and filter replacement reminders.

System Compatibility & Setup

Honeywell T9

Both thermostats are designed for self-installation, so you can set them up without professional help in most cases. Honeywell T9 requires a C-wire for installation, but a C-wire Adapter comes included to accommodate homes without an existing C-wire. The Nest Learning Thermostat (4th Gen), on the other hand, can work without a C-wire.

Both the Honeywell T9 and Nest Learning Thermostat (4th Gen) are compatible with multi-stage heating, multi-stage cooling, fan, and heat pump systems.

Nest Learning Thermostat (4th Gen) also supports 1-wire or 2-wire humidifiers, dehumidifiers, and ventilation, which the Honeywell T9 does not. This wider compatibility and flexibility gives Nest an advantage for homes with more complex HVAC setups.