What Sentry Mode Costs Your Tesla Battery

Published October 23, 2026 · Last reviewed October 23, 2026

Measure it before you decide

There is no honest universal number for this. The drain depends on the model, the software version, the temperature, whether the car is awake for other reasons, and how often something nearby triggers recording. Guessing leads either to needless worry or to a flat battery at the airport. A two-day test takes no effort and gives you your own figure.

Action

Run a baseline day. Switch Sentry Mode off, park the car for about 24 hours without driving or charging, and note the battery percentage at the start and the end.

Why it helps

Even a sleeping car loses a little charge, and temperature changes that figure. You need the no-Sentry number to isolate what Sentry adds.

Verification

You have two readings, taken from the touchscreen or the Tesla app, with the exact hours between them. Reading the app can wake the car, so look sparingly.

Action

Run a Sentry day. Repeat the same test in the same place with Sentry on. Find the switch under Controls › Safety › Sentry Mode, noting that menu names move between releases.

Why it helps

Same place and similar weather make the two days comparable.

Verification

The difference between the two days is the extra percentage Sentry costs per 24 hours.

Action

Convert it to range you care about. Divide your car's displayed range at the start by its battery percentage to get miles per point, then multiply by the extra points Sentry used.

Why it helps

Percentages hide the real cost. Range lost is what changes your next trip.

Verification

You can state the cost as a number of miles per day, for example “about this many miles per parked day”.

Action

Turn Sentry off where the car sits unattended for days, such as airport long-stay parking, unless you are certain you can return to a charged car. Profile C

Why it helps

The drain is per hour, so a week of parking multiplies it. A car that returns to a low battery needs a charge before you can drive it anywhere.

Verification

Your plan shows you arriving home with enough charge to reach a charger, with margin.

Action

Check the Sentry exclusion options in your menu, if your software offers them, so the car does not run Sentry at home or other trusted places.

Why it helps

The risk differs by place. Spending battery watching a locked garage may not be worth it.

Verification

Sentry shows as active at the places you chose and off at the ones you excluded. Profile A

Where it is worth leaving on

Treat Sentry as insurance with a running cost. It is more sensible in a place with a history of break-ins or door dings, for short stays, or when you are plugged in and the cost is paid by the wall. It is less sensible for multi-day parking, when the battery is already low, and in cold weather when the pack has less to give. Profile B, D

Other things that keep a car awake

Sentry is not the only reason a parked Tesla uses charge. Features such as cabin overheat protection, keeping the climate on, frequent app refreshes and some third-party apps that poll the car can all wake it. If your baseline day shows an unexpectedly large loss, switch these off one at a time and repeat the test.

What Sentry does and does not do

Sentry records and alerts; it does not stop anyone doing anything. Saved footage usually needs a suitably formatted USB drive, so check the manual for the requirements on your car. Cameras that record people nearby may be subject to local privacy rules, so check yours.

How it works

A parked Tesla can drop into a low-power sleep state in which most of its computers are off and it uses very little energy. Waking the car, whether by opening the app, unlocking a door or running a scheduled task, brings the main computer up and keeps it up for a while before it sleeps again.

Sentry Mode works by preventing that deep sleep. The exterior cameras and the processing that watches them must stay on to notice something approaching the car, so the car runs in a middle state: not driving, not asleep. In that state it consumes energy continuously, and it spends more whenever it records. Because the cost is steady, it grows with time parked, not with how much happens.

That is why the same setting feels harmless for an evening at a restaurant and troublesome after a week at the airport. The car also reduces features at low battery to protect itself, and the manual describes how your software handles Sentry then. Measuring your own baseline and Sentry days takes the guesswork out of that, because you see how many points per day the setting really costs on your car.

Worked example

Suppose, as a hypothetical, that your baseline day with Sentry off goes from 80% to 79%, one point in 24 hours. The Sentry day goes from 80% to 72%, eight points. Sentry therefore cost seven extra points per day.

Suppose your car shows 240 miles of range at 80%. That is 3 miles per point, so the seven extra points are about 21 miles of range per parked day. A five-day business trip with the car parked at the airport and Sentry on would cost about 105 miles, or 35 points.

With that information the decision is easy. At a downtown parking garage for four hours, the cost is small and you may keep Sentry on. At the airport for five days, you turn it off and return to a car that has lost only a few points. All of these figures are invented to show the arithmetic; yours will differ, which is why you measure.