Quick answer: ecobee (Premium or Enhanced, ~$229–299 CAD) is the best overall pick for dual-fuel systems. It has the most explicit built-in support for managing the heat pump/furnace switchover of the mainstream smart thermostats. Before buying anything, confirm your installer’s staging and aux-heat lockout settings so the thermostat’s switchover logic matches how your system was designed to run.

What a Dual-Fuel System Is

A dual-fuel (also called “hybrid heating”) system pairs a heat pump with a gas or oil furnace as backup. The heat pump handles heating for most of the season, since it’s typically cheaper to run per unit of heat above a certain outdoor temperature. When outdoor temperatures drop low enough that the heat pump becomes less efficient (or its output capacity drops), the system switches over to the furnace to take over primary heating duty.

This differs from a simple heat-pump-with-electric-backup system (common in the US, less common in Canada). In a true dual-fuel setup, the backup heat source is a separate fuel-burning furnace, not electric resistance coils. The switchover point, the outdoor temperature at which the system hands off from heat pump to furnace, is a real, configurable setting, sometimes called the balance point.

Why the Thermostat Matters More Here

With a single-fuel system, the thermostat’s main job is simple: call for heat, system responds. With dual-fuel, the thermostat makes an ongoing decision about which heat source should be running, based on outdoor temperature, how close the system is to the setpoint, and how the installer configured the switchover logic. A thermostat that handles this well reduces your heating costs by keeping the cheaper heat pump running longer before handing off to furnace backup. A thermostat that handles it poorly can trigger the furnace too early (wasting the point of having a heat pump) or too late (leaving you underheated on cold days).

Dual-fuel homeowners should pay more attention to thermostat choice than single-fuel homeowners for this reason: the thermostat manages which of two heating systems runs at any given moment.

Best Overall: ecobee

Price: ~$229–299 CAD | C-wire required: No (PEK included) | Warranty: 3 years

ecobee has the most explicit, well-documented dual-fuel and auxiliary-heat support among the mainstream smart thermostats covered on this site. During setup, it asks whether your system is a dual-fuel configuration and walks through configuring the switchover behavior rather than treating it as an edge case. It supports setting temperature-based switchover points and aux-heat lockout thresholds, the two settings that control when the system hands off from heat pump to furnace.

ecobee Premium’s SmartSensors are also useful in a dual-fuel context: dual-fuel systems are common in homes trying to balance comfort and cost in variable climates, and room-level temperature data helps the thermostat make switchover decisions instead of reacting only to one reading at the thermostat itself.

Note on aux-heat settings: ecobee’s software can only manage switchover logic within the parameters your HVAC system allows and however your installer wired and configured the aux-heat relay. A misconfigured aux-heat lockout at the equipment level limits what the thermostat can control (see below).

Full review: ecobee Smart Thermostat Review

For heat-pump-specific buying guidance beyond dual-fuel setups, see: Best Smart Thermostats for Heat Pumps & Mini-Splits

What to Check Before Buying

Dual-fuel is one of the few cases on this site where we’d recommend confirming a few technical details before purchase rather than picking based on price and features alone:

  • Staging configuration: Ask your installer (or check your existing thermostat’s settings, if accessible) how many stages your furnace backup has, and whether the current thermostat is configured to match. A mismatch here can cause the furnace to run less efficiently than intended.
  • Aux-heat lockout temperature: This is the outdoor temperature below which the system is allowed to bring in furnace backup. If it’s set too high, you’ll burn furnace fuel more than necessary; too low, and you risk underheating on cold days before the furnace kicks in.
  • Balance point vs. economic balance point: Some installers set the switchover based on when the heat pump physically can’t keep up (balance point), others factor in relative fuel costs (economic balance point: switch over whenever the furnace costs less to run than the heat pump at current utility rates). ecobee can be configured for either approach, but it needs the right inputs from you.
  • Whether your current thermostat has this configured correctly: if you’re upgrading from another smart or programmable thermostat, get its current dual-fuel settings before replacing it, so you can replicate (or improve) the configuration rather than starting from a generic default.

If any of this is unclear, call your HVAC installer or a technician before or during setup. Dual-fuel is one system type where “set it up and see what happens” can cost real money over a winter.

See also: Smart Thermostat Compatibility: Will It Work With My System?

Dual-fuel picks: ecobee Premium, ecobee Enhanced (dual-fuel/aux-heat support, staging configuration, balance point settings, price, warranty)

Frequently Asked Questions

What is a dual-fuel heating system?
A dual-fuel (hybrid) system pairs a heat pump with a gas or oil furnace as backup. The heat pump handles most heating; the system switches over to the furnace when outdoor temperatures drop low enough that the heat pump becomes less efficient or can’t keep up with demand.

What’s the best smart thermostat for a dual-fuel system?
ecobee is the best overall pick. It has the most explicit built-in support for configuring switchover logic, staging, and aux-heat lockout settings among mainstream smart thermostats. Confirm your installer’s staging and switchover configuration before or during setup regardless of which thermostat you choose.

What is a balance point in a dual-fuel system?
The balance point is the outdoor temperature at which the system switches from heat pump to furnace backup. It can be set based on when the heat pump physically can’t keep up (a capacity-based balance point) or on relative fuel costs (an economic balance point). Your installer sets this during installation; verify it’s configured correctly when installing a new thermostat.

Can any smart thermostat control a dual-fuel system?
Many smart thermostats support dual-fuel wiring, but not all handle the switchover logic equally or make it easy to configure. ecobee has the most explicit dual-fuel setup flow among mainstream options. Verify a specific thermostat’s dual-fuel documentation before assuming basic compatibility is enough.

Will a smart thermostat lower my dual-fuel heating costs?
It can, by keeping the more efficient, cheaper heat source running longer before handing off, if the switchover settings are configured correctly. The savings depend on correct staging and balance-point configuration rather than the thermostat brand alone: a well-configured budget thermostat can outperform a premium one configured incorrectly.

Do I need a C-wire for a smart thermostat on a dual-fuel system?
Most dual-fuel systems have enough wiring complexity (multiple stages, aux-heat wires) that a C-wire is common, but ecobee’s Power Extender Kit can still help in some no-C-wire setups. Given the added wiring complexity of dual-fuel systems, confirm your specific wiring with an installer rather than assuming a no-C-wire solution will cover every terminal your system uses.