What should I set my thermostat to in winter?

Winter here is the easy season, which is exactly why the thermostat matters: a mild climate means your setback choices, not the weather, decide most of the gas bill. This page is the January companion to the summer setpoint answer.

The reference numbers: the Department of Energy recommends 68 degrees while you are home and awake, and lowering it while you sleep or leave. Their arithmetic: roughly 1 percent saved on heating for each degree of setback held 8 hours, and a 7 to 10 degree setback for 8 hours a day trims up to 10 percent off the year’s heating cost. Sleeping at 60 to 62 under a real blanket is free money, and Bakersfield nights rarely get cold enough to make it a hardship.

Why this works even better here than the national math suggests: heat loss scales with the gap between inside and outside. Against a 38 degree tule fog morning, the gap at 68 is thirty degrees; drop the house to 60 overnight and you have cut the driving force by more than a quarter for those hours. Same physics as the summer leave-it-on-all-day myth, running in reverse.

The heat pump exception, and it matters: if your heat is a heat pump, skip the deep setbacks. A big morning recovery can push some systems into their electric backup heat, which burns through the savings the setback earned. Heat pump owners do better with modest setbacks of a few degrees, or a smart thermostat with heat pump logic, $240 to $420 installed, that ramps recovery gently. If you are not sure which you have, this explainer sorts it in one minute.

The honest footnote: 68 is a reference point, not a rule of virtue. Some houses hold 66 comfortably, some households need 71, and drafty ducts can make any setpoint feel wrong, which is its own fixable problem. Set the schedule once, let it run, and spend your attention on the setback hours, because that is where the bill is actually decided.