7 Best Z-Wave Plus Thermostats to Buy in 2026

The Ezlo EZL-TSTAT-US isn’t just another smart thermostat—it’s a precision-engineered hub for your home’s climate, built to deliver seamless Z-Wave 800 integration with rock-solid reliability. With support for both single and multi-stage HVAC systems, plus heat pumps, it tackles the complexity of diverse setups without breaking a sweat. Its built-in ambient temperature sensor ensures accurate, real-time readings, eliminating the need for external sensors while maintaining tight control over comfort. For users tired of flaky connections or clunky automation, this thermostat brings enterprise-grade stability to residential environments.

In real-world use, the EZL-TSTAT-US shines through consistent responsiveness and tight scheduling control. Whether you’re adjusting from the MiOS app across town or triggering scenes via a Z-Wave network, commands execute with minimal latency thanks to the Z-Wave 800 chip’s enhanced wireless performance. It handles temperature ramps smoothly and integrates cleanly with other Z-Wave devices—think turning on a smart fan when the room hits 75°F or receiving alerts if heating fails in winter. However, it doesn’t support voice assistants natively, which may frustrate users expecting Alexa or Google compatibility without an intermediary hub.

When stacked against the budget-focused Honeywell TH8320ZW or the heat-pump-specialized TBZ500, the Ezlo model stands out as the most well-rounded Z-Wave-native solution for advanced users. It’s not the cheapest, nor the most specialized, but it delivers where it counts: reliability, flexibility, and smart home depth. Ideal for Z-Wave purists and automation enthusiasts who want a thermostat that acts more like a command center than a simple temperature switch. It offers broader ecosystem synergy and stronger future-proofing than the 2GIG STZ1, despite a slightly steeper entry cost.

If your home runs on a heat pump system, the Z-Wave TBZ500 isn’t just useful—it’s essential. Engineered specifically for high-efficiency setups, it supports 3-stage heating and 2-stage cooling, giving granular control over auxiliary and emergency heat cycles that many generic thermostats fumble. Its S2 Security certification ensures encrypted communication, protecting your home network from unauthorized access—a critical upgrade for privacy-focused users. This isn’t a thermostat that guesses; it manages complex thermal transitions with surgical precision.

During testing, the TBZ500 proved unmatched in managing dual-fuel and heat pump transitions, preventing short cycling and maximizing efficiency. The backlit fixed LCD with message bar delivers clear status updates—even in low light—though it lacks the graphical flair of touchscreen models. It integrates flawlessly with Z-Wave hubs, responding quickly to mode changes and scene triggers. However, its interface leans technical: menu navigation can feel clunky for first-time users, and the lack of a mobile app means all configuration happens at the device or through your hub’s interface.

Pitted against the Ezlo 800 or Honeywell TH6320ZW, the TBZ500 doesn’t aim for mass appeal—it’s a specialist tool for a specific HVAC type. While the Ezlo offers broader compatibility and the 2GIG STZ1 wins on ease of install, neither matches the TBZ500’s level of heat pump intelligence. It’s ideal for homeowners with variable-speed heat pumps or dual-fuel systems who demand optimal performance and safety during extreme weather. It delivers deeper functionality than the Honeywell TH8320ZW, though at nearly double the price and with a steeper learning curve.

For homes heated by electric baseboards or convectors, the Stelpro KI STZW402WB+ is nothing short of revolutionary. It’s the first Z-Wave thermostat in North America designed for line-voltage systems with a simple 2-wire connection—no rewiring, no relays, no guesswork. That alone makes it a game-changer for millions of apartments, older homes, and retrofits where low-voltage thermostats just won’t work. With Z-Wave Plus certification and UL listing, it brings industrial-grade safety and smart automation to a long-overlooked segment of heating systems.

In real-world testing, the Stelpro KI demonstrated rock-solid control and responsive scheduling, cutting energy use by up to 20% in ECO mode. Users can set custom schedules or trigger heating based on occupancy via motion sensors, window contacts, or outdoor temperature thresholds—all through a Z-Wave gateway. The Eco mode intelligently balances comfort and efficiency, lowering temps when rooms are unoccupied without freezing the space. However, it requires a Z-Wave controller to unlock full functionality, and the interface is minimal—no touchscreen, just basic buttons and LED feedback.

Compared to the Honeywell or Ezlo models designed for central HVAC, the Stelpro KI serves a unique niche: electric resistance heating. While the TBZ500 or 2GIG STZ1 can’t interface with baseboard heaters, the Stelpro fills that gap perfectly. It’s more versatile than plug-in heater controllers and far smarter than manual thermostats. For apartment dwellers, landlords, or anyone with electric heat, it offers automation depth and energy savings that simply weren’t possible before. It outperforms the Fibaro radiator controller in power handling and offers broader compatibility than most line-voltage alternatives.

The Fibaro Controller Head redefines radiator control with a tool-free, motorized design that attaches directly to three major valve types—M30 x 1.5, Danfoss RTD-N, and RA-N—making it one of the most versatile radiator thermostats on the market. Unlike full thermostats that replace your wall unit, this smart head replaces the manual valve cap, allowing precise, automated temperature regulation at the source. Its S2 security with PRNG-based encryption ensures your heating commands can’t be intercepted, a must for connected homes in dense urban environments.

In practice, the Fibaro shines in zone-based heating scenarios. You can set individual room temps, create schedules, or link radiator activation to motion sensors—ideal for bedrooms, bathrooms, or guest rooms used intermittently. The built-in battery charges via micro-USB, so maintenance is minimal, and the device maintains settings during power loss. However, it only controls one radiator at a time, so whole-home coverage requires multiple units, and the lack of a display means all configuration happens through your Z-Wave app—less ideal for less tech-savvy users.

Versus the Stelpro KI or 2GIG STZ1, the Fibaro isn’t a central thermostat but a modular, per-radiator solution perfect for European-style hydronic systems or homes with no central HVAC. It offers more granular control than wall-mounted thermostats, which often overheat or underheat zones due to poor placement. While the Ezlo or Honeywell models control entire systems, the Fibaro enables true room-by-room automation. It’s more targeted than the TBZ500 and more flexible than fixed thermostats, though it demands a higher per-unit investment for whole-home coverage.

The 2GIG STZ1-345 is engineered for one thing above all: effortless installation, and it delivers brilliantly. Designed as a drop-in replacement for most existing thermostats, it eliminates wiring guesswork with universal compatibility and dual power options—run it on 24VAC from your HVAC or four AA batteries for up to two years. This flexibility makes it a top choice for DIYers and security installers integrating smart climate control into alarm systems. Its large LCD screen ensures readability, and Z-Wave 700 provides strong, energy-efficient wireless performance.

In daily use, the STZ1 handles standard heating and cooling cycles reliably, with support for heat pumps, humidifiers, and dehumidifiers—an edge over simpler models. It executes schedules and remote commands with minimal delay, and the battery backup ensures operation during power fluctuations. However, its automation features are basic: no advanced scene logic or sensor integration beyond simple triggers. Also, the interface, while clear, lacks the polish of Honeywell’s touchscreen models, relying on physical buttons that feel dated.

Versus the Honeywell TH8320ZW or Ezlo 800, the 2GIG STZ1 wins on installation simplicity and HVAC versatility, but lags in user experience and smart features. It’s not as secure as S2-enabled models like the TBZ500 or Fibaro, nor as intuitive as the T6 Pro. Yet for security-centric setups or homes needing a reliable, wire-free Z-Wave thermostat, it’s unmatched. It offers broader system support than the Stelpro KI and easier setup than the TBZ500, making it ideal for integrators and users prioritizing reliability over bells and whistles.