Phase 1 — Inspect and schedule (early fall, before the first freeze)

Book a professional furnace or boiler inspection now, before the first cold snap.Getting your furnace checked by a technician now could save you from an emergency when it's really cold outside; a technician should confirm the pilot light and thermostat are working and check for leaks or cracks as well as the efficiency of your furnace.
Have the chimney inspected before first use — a blocked or cracked flue causes chimney fires and carbon monoxide backup. if plan to use fireplace or wood stoveIf you're planning on using your chimney this winter, make sure to get it inspected; you can ask your local fire department to recommend an inspector.
Inspect the roof, flashing, and shingles for damage.Examine windows, doors, and rooflines and inspect for cracked panes, loose seals, missing shingles, or damaged flashing — addressing small issues early helps prevent leaks and costly water damage when snow and ice accumulate.
Locate your main water shutoff valve and test that it fully closes — a stuck valve is useless in a burst-pipe emergency.Find your water shutoff valve, test the valve to make sure it's not stuck and that you can shut it off in an emergency, and if you can't, contact a plumber to replace it.

Phase 2 — Seal the envelope and insulate

Add weatherstripping and window film to doors and windows.Weatherstripping includes things like window insulator kits and foam for your doors and windows — one way to keep cold air from coming into your home.
Caulk or foam gaps around vents, pipe penetrations, and crawl-space openings.
Top up attic insulation.Add or replace insulation in your attic — insulating your attic can save you a significant amount on heating costs.
Insulate exposed pipes in unheated spaces (garage, crawl space, exterior walls) — these freeze first.Add insulation to exposed pipes, attics, and basements where freezing is most likely to occur.

Test every smoke and carbon monoxide alarm and replace weak batteries.It's always good to check your smoke and carbon monoxide detectors twice a year — check your detectors, replace the batteries if needed, and keep you and your family safe.
Replace the furnace air filter, then repeat every 1–3 months through the season.Change the air filter on your heating system regularly (usually every 1-3 months).
Use only space heaters with an automatic shut-off, and keep them clear of anything combustible. if using space heatersConsider purchasing a space heater or electric blanket — just make sure they have an auto-shutoff switch, and remember to follow best practices for space heater safety.
Install or program a thermostat to hold steady heat and trim costs.Consider installing a programmable thermostat to optimize your heating schedule.

Disconnect, drain, and store all garden hoses, then drain outdoor spigots — trapped water is the classic cause of a burst supply line.Don't forget to drain water heaters, toilets, and outdoor spigots.
Let a faucet drip and open cabinet doors under sinks on exterior walls to keep water moving and pipes warmer. if during a hard freeze
Winterize the pool, and run the pump during sub-freezing spells. if if you have a poolWinterize your pool and check your coverage — if the temperatures dip below freezing, run the pump to keep the pipes from freezing.

Clear gutters and downspouts of leaves and debris to prevent ice dams and overflow.Verify that gutters and downspouts are clear of debris to promote proper drainage.
Insulate crawl spaces and the basement rim to stop cold-air infiltration.Insulate crawl spaces and basements to prevent cold air from creeping in.

Set the thermostat to at least 50–55°F rather than off, to keep pipes above freezing.Set thermostats (don't turn it off) at the lowest temperature (at least 50 to 55 degrees) to prevent pipes or anything else from freezing.
Shut off water at the main valve, then open faucets to drain the lines.Shut off the water at the main valve to prevent unwanted pressurized water getting inside your home, then open all faucets, allowing water to drain from your pipes after you shut off the main.
Drain the water heater and interior pipes to prevent flooding. if utilities disconnected or long absenceDrain the water heater and interior pipes — this helps prevent flooding.
Add non-toxic antifreeze to drain traps and toilet bowls once lines are drained.Adding non-toxic antifreeze to drain traps and toilet bowls provides additional protection against freezing temperatures.
Ask a neighbor to watch the property and report any damage.Inform neighbors of your time away and ask them to watch out for your home and report any unusual activity or damage.