Schedule vs geofencing
Use a schedule if your week is predictable: the thermostat changes temperature at fixed times and can start early so the house is ready. Use geofencing if your comings and goings vary: your phone tells the thermostat when the last person leaves and the first returns. Some brands let you combine them; Sensi makes you pick one.
What is the difference between a schedule and geofencing?
A schedule runs on the clock. You set times and temperatures for each part of the day, and the thermostat follows them whether or not anyone is home. The Honeywell Home T5, T5+ and T6 Pro Wi-Fi, for example, have four periods per day: Wake, Away, Home and Sleep.
Geofencing runs on phone location. The app watches the phones in the household and switches the thermostat to its away temperature when the last one leaves a boundary around the home, then back when the first one returns. Sensi puts that boundary at 3 miles. On Honeywell Home you draw it yourself in the Resideo app. How each brand handles the details is on the thermostat geofencing page.
| Schedule | Geofencing | |
|---|---|---|
| What triggers a change | The time of day | Phones crossing a boundary around the home |
| Best fit, according to Sensi | A predictable routine from day to day or week to week | A busy person with no set schedule |
| Getting the house ready | Can start early so the house is at temperature on time | Starts when the first phone comes back inside the boundary |
| Needs | A correct clock on the thermostat | Wi-Fi, the app on each phone, location set to always allowed |
| Main weakness | Sets back on schedule even when someone stays home | Wrong guesses when a phone is left behind, switched off or not enrolled |
When is a schedule the better choice?
When your week repeats. Sensi's advice is that if you have a predictable schedule from day to day or week to week, scheduling may fit better. A schedule also has one advantage geofencing cannot match: it knows what happens next. Many thermostats use that to start heating or cooling early so the house reaches the next setpoint on time; recovery mode explains how.
A schedule also works for people who do not carry a phone with the app, such as children or a visiting relative, because nobody needs to be enrolled. And it keeps running if the internet drops. The Honeywell Home T9 guide notes that location-based temperature control is managed through the Resideo app and will not function without a Wi-Fi connection.
The downside is rigidity. If you stay home on a weekday, the Away period still arrives. You can override it with a hold, but someone has to remember.
When is geofencing the better choice?
When your days vary. Sensi says geofencing lets a busy person with no set schedule save energy without remembering to adjust the thermostat. It follows the household rather than the clock, so a day off or a late return is handled without editing anything.
Its accuracy depends on everyone's phone. Honeywell Home lists what has to be right: location access set to "Always" on iOS or precise location allowed on Android, the app allowed to run in the background, battery optimization apps told to leave it alone, and a separate account for each phone. Honeywell also suggests keeping the boundary clear of roads you drive past without heading home.
Recovery is the other limit. The thermostat only learns you are coming back when your phone crosses the boundary, so a short boundary leaves little time to warm or cool the house. Google addresses this on the Nest Learning Thermostat (4th gen) and Nest Thermostat (2020) with "Schedule pre-heating and cooling", which pre-heats or pre-cools for upcoming scheduled temperatures while you are away, then goes back to Eco if nobody comes home.
Can you combine them?
On several brands, yes, and that often works best: a schedule for the predictable parts of the day, location to catch the exceptions.
- Honeywell Home T9. The guide offers location-based control, time-based scheduling, or a combination. Smart Scheduling adds a Sleep period to geofencing.
- Google Nest. Eco when away sits on top of the regular schedule. When someone comes home, the thermostat goes back to its normal schedule. See Nest Eco turning on by itself.
- ecobee. Smart Home & Away uses occupancy sensors rather than phones, and ecobee says it follows your ecobee schedule: it can override a Home period to Away, or an Away period to Home.
- Amazon Smart Thermostat. You can run a schedule in the Alexa app with the "Use thermostat schedule" switch and also set an away temperature under Alexa automatic control. See Alexa Hunches on the Amazon Smart Thermostat.
Sensi is the exception. It says you can have a programmed schedule or geofencing (or no schedule), and only one can be on at a time.
Does geofencing change how holds work?
On some models. On the Honeywell Home T5, T5+ and T6 Pro Wi-Fi, permanent hold is disabled while geofencing is on. On the T9, a manual change lasts until you cross the geofence. Under a schedule, a manual change usually lasts until the next period instead. If your changes keep disappearing, see thermostat keeps returning to its schedule.
Frequently asked questions
- Can I use a schedule and geofencing at the same time?
- On some thermostats. The Honeywell Home T9 guide says you can use location-based control, a time-based schedule, or a combination of both. Sensi says only one can be on at a time. On Google Nest, Eco when away works on top of the regular schedule.
- Will geofencing have the house warm when I get home?
- Only if the drive from the edge of the boundary is long enough for the system to catch up. The thermostat starts recovering when you cross back in. A schedule can start early instead, because it knows the time in advance.
- Does geofencing work without Wi-Fi?
- No. The Honeywell Home T9 guide says location-based temperature control is managed through the Resideo app and will not function without a Wi-Fi connection. A schedule stored on the thermostat keeps running from its own clock.
- Which saves more energy?
- None of the manufacturers we checked publishes a comparison. Geofencing can catch absences a schedule misses, such as an unplanned day out. A schedule sets back at the same time every day even if someone stays home.