7 Best Z-Wave Smart Thermostats to Buy in 2026

The Honeywell Home T6 Pro isn’t flashy, but it’s a precision-engineered workhorse built for Z-Wave purists who demand reliability over Wi-Fi gimmicks. With Z-Wave certification, UWP mounting compatibility, and support for up to 3-stage heating and 2-stage cooling, it handles complex HVAC setups like heat pumps and dual-fuel systems with quiet confidence. Its non-Wi-Fi design eliminates connectivity bloat, making it ideal for users prioritizing stability and security in their smart home ecosystem—especially those integrating through a Z-Wave hub rather than cloud apps.

In real-world use, the T6 Pro delivers consistent, accurate temperature control across diverse climates and system types. The backlit touchscreen remains responsive in low light, and scheduling is intuitive whether adjusting manually or via the Honeywell Home app through a compatible gateway. It draws power from a standard 24VAC system, ensuring continuous operation without battery anxiety. However, remote access hinges entirely on your hub’s reliability, and users without a robust Z-Wave network may find setup less plug-and-play than Wi-Fi alternatives.

Compared to the Ezlo EZL-TSTAT-US, the T6 Pro trades app-centric convenience for superior HVAC flexibility and build quality—a clear win for advanced users with multi-stage systems. It also outclasses the 2GIG-STZ1-345 in system support, though both share strong Z-Wave integration. This is the thermostat for home automation veterans who want a rock-solid, future-proof controller that plays well with others—without sacrificing control depth. It offers more granular system support and better hardware integration than budget-focused models, just without app-first polish.

If you’re battling sticky summers or damp basements, the 2GIG-STZ1-345 stands out as a humidity-hunting specialist in a sea of basic temperature controllers. Powered by Z-Wave 700-series technology, it delivers longer wireless range and rock-solid mesh stability, making it perfect for larger homes or systems with signal obstacles. Its standout feature? Direct control of humidifiers and dehumidifiers, a rare capability that lets you fine-tune indoor air quality, not just temperature—ideal for allergy sufferers or climates with extreme moisture swings.

In daily operation, the thermostat proves remarkably self-sufficient: it runs on 4 AA batteries for up to two years or can tap into your HVAC’s 24VAC power, giving installers flexibility. The large, clear LCD makes scheduling and mode changes easy, and the drop-in replacement design means most users can swap out an old thermostat in minutes. It handles standard gas/electric and heat pump systems without issue, though it lacks support for advanced multi-stage configurations found in the Honeywell T6 Pro. No SmartStart or S2 security means slightly less convenience and protection than newer Z-Wave Plus models.

Next to the Stelpro KI, this unit supports broader HVAC types but doesn’t touch line-voltage systems. Against the Ezlo EZL-TSTAT-US, it offers better standalone usability and humidity integration, though with fewer app-driven automations. This is the go-to for homeowners who want Z-Wave reliability with added climate intelligence—especially where moisture control matters. It delivers more environmental awareness and easier installation than most, just without the latest security or app depth.

When it comes to heat pump mastery, the TBZ500 doesn’t just compete—it dominates. Engineered specifically for complex heat pump systems, it supports 3-stage heating and 2-stage cooling, plus emergency heat selection right from the thermostat, giving users full command without relying on external controls. Its Z-Wave Plus certification and S2 security ensure secure, stable communication within your smart home network, while the 7-character message bar delivers clear status updates—like system mode or alerts—without cluttering the fixed LCD.

In practice, the TBZ500 excels in cold-climate performance, where heat pumps cycle frequently and demand precise staging. It integrates seamlessly with Z-Wave hubs, enabling automated scenes based on temperature, time, or occupancy, and its 24VAC power requirement means no battery distractions. The backlit display is easy to read at night, though the interface leans utilitarian—more industrial control panel than sleek consumer gadget. It doesn’t support line-voltage systems, so it’s not for baseboard-only homes, and the lack of Wi-Fi or app-native control means full functionality depends on your hub.

Stacked against the Honeywell T6 Pro, the TBZ500 offers deeper heat pump optimization and better emergency heat handling, though with a less polished UI. Compared to the Ezlo EZL-TSTAT-US, it provides more granular control for hybrid systems. This is the thermostat for homeowners with heat pump-centric HVAC who want maximum efficiency and automation without compromise. It delivers superior heat pump logic and system-specific tuning over generalist models, just with a steeper learning curve.

For those who live in their smart home app, the Ezlo EZL-TSTAT-US is a remote control powerhouse that turns your phone into a climate command center. Built on Z-Wave 800 Series technology, it offers ultra-low latency and strong mesh performance, while native integration with the MiOS app lets you adjust schedules, monitor temperature, and trigger automations from anywhere—no extra hub layers. The built-in ambient sensor ensures accurate readings, and the ability to create smart scenes with other Z-Wave devices makes it a natural fit for automated homes.

In real-world use, it handles single and multi-stage HVAC systems with ease, including heat pumps, and maintains consistent temperature transitions without overshoot. Scheduling works even when not connected to a Z-Wave network, adding flexibility during setup. However, the display is basic, and manual wall controls feel like an afterthought compared to the rich app experience. It requires a 24VAC C-wire, which may complicate installation for older systems, and lacks humidity control—missing a key feature found in the 2GIG models.

Versus the 2GIG-STZ-1, the EZL-TSTAT-US wins on app experience and automation depth, though it falls short on security with no S2 authentication. Compared to the Honeywell T6 Pro, it’s more app-centric but less HVAC-flexible. This is the ideal pick for users who want seamless remote access and scene-based automation without juggling multiple apps. It delivers better app integration and smarter triggers than most, just with fewer physical controls and environmental sensors.

The Stelpro KI STZW402WB+ is a game-changer for electric heating, standing alone as the first Z-Wave thermostat in North America designed for line-voltage baseboard and convector systems. With its 2-wire connection directly to heaters, it eliminates the need for relays or complex conversions, making smart control accessible to thousands of homes previously locked out of automation. Z-Wave Plus certification ensures reliable mesh networking, while UL certification and Canadian design speak to its safety and durability in real-world installations.

In practice, it delivers precise, silent control over electric heating zones, with ECO mode helping users cut energy use by up to 20% through intelligent scheduling. The fixed B/W LCD is clear and functional, and when paired with a Z-Wave gateway, it enables advanced automations—like turning on heat when a door sensor detects entry or adjusting based on motion. It doesn’t support gas or heat pump systems, so it’s not a whole-home solution for mixed HVAC setups. Also, gateway sold separately means added cost and setup complexity for beginners.

Compared to the Honeywell and 2GIG models, the Stelpro KI serves a unique niche: it’s the only one built for line-voltage electric systems, making it irreplaceable for apartments, condos, or supplemental heating zones. While the Ezlo and Honeywell models dominate in forced-air environments, this one owns the electric space. For rental properties, retrofit projects, or all-electric homes, it offers unmatched compatibility and automation potential where others simply can’t go.