The lights go out without warning. One moment the house is humming — fridge, heating, Wi-Fi, phone chargers — and the next it is dark, silent and getting colder. An outage can last an hour or several days, and the difference between a miserable night and a dangerous one is usually decided before the power fails. Preparation is a short list of supplies, a plan the household understands, and a handful of safety rules. If a winter storm is on the way, pair it with our winter storm preparedness guide and how strong power lines are in snow.
What a power outage can disrupt
Ready.gov defines an outage simply: the electrical power goes out unexpectedly. What follows can reach far beyond the lights. It may disrupt communications, water and transportation, close shops, petrol stations, cash machines and banks, cause food spoilage and water contamination, and prevent the use of medical devices that rely on mains power. An extended outage may affect a whole community. That is why every emergency agency starts in the same place: assume you may need to manage on your own for several days. The American Red Cross recommends storing at least two weeks of food and water at home; the Canadian and British Red Cross advise families to be self-sustaining for at least three days.
Start with an inventory of what needs electricity
Ready.gov’s first step is the one most people skip: list the items you need that rely on electricity. Walk through your home with a notepad. The list is usually longer than expected: fridge and freezer, heating and its fan or pump, water heater, well pump if you have one, lights, phones and laptops, the Wi-Fi router, the garage door opener, the oven, medical devices such as a CPAP machine, and refrigerated medicines such as insulin. Then plan batteries or another power source for the items that matter most, such as a portable charger for phones. If anyone depends on electrically powered medical equipment, talk to your medical provider about an outage plan, and ask your electricity supplier what support it offers — in the UK, vulnerable customers can join the Priority Services Register.
Build a kit before you need it
A power outage kit is mostly light, information, food, water and warmth — ordinary things, gathered in one place before the dark arrives. Ready.gov’s Build a Kit list recommends one gallon of water per person per day for several days, a several-day supply of non-perishable food, a flashlight with extra batteries, a battery-powered or hand-crank radio (plus a NOAA Weather Radio with tone alert in the US), a first aid kit, a manual can opener, and a phone with chargers and a backup battery. For outages specifically, Ready.gov adds a flashlight for every household member and carbon monoxide detectors with battery backup on every level of your home. The Red Cross guidance is blunter: use flashlights, not candles — candles cause house fires every winter. Keep a torch for every person, plus spare batteries, where everyone can find them in the dark. Add a portable phone charger, kept charged, and a paper copy of emergency contacts. Keep blankets and warm layers easily accessible, and keep a small amount of cash at home, because card machines and cash points may not work.
Food and water: the numbers that matter
Food safety during an outage comes down to three numbers, agreed by Ready.gov, the Red Cross and food safety authorities. Keep freezers and refrigerators closed. A refrigerator keeps food cold for about four hours with the door shut. A full freezer keeps its temperature for about 48 hours, or about 24 hours if half full. The Canadian Red Cross gives a more cautious freezer range of 24 to 36 hours, so plan on the shorter figure. Throw out food if its temperature is 40°F (about 4°C) or higher — Ready.gov advises discarding food exposed to that temperature for two hours or more, and US guidance says to discard refrigerated perishables such as meat, poultry, seafood, milk, eggs and leftovers above 40°F for four hours or more. When in doubt, throw it out. Freeze bottles of water in advance if bad weather is forecast — they keep the freezer cold longer and give you drinking water as they melt. Stock food that needs no cooking: tinned beans and fish, peanut butter, crackers, dried fruit, nuts and cereal bars, plus a manual can opener.
Carbon monoxide and generator safety
Carbon monoxide is the most dangerous part of a power outage, and it is invisible — a colourless, odourless gas that can kill you, your family and your pets. It is produced by anything that burns fuel: generators, camp stoves, charcoal grills and gas heaters. The rules from Ready.gov, the Red Cross and the US Consumer Product Safety Commission are absolute. Generators, camp stoves and charcoal grills should always be used outdoors, at least 20 feet (about six metres) from windows, doors and vents, with exhaust pointed away from the house. Never run a generator in a home, garage, basement, crawlspace or shed, even with doors or windows open. Never use a gas stove or oven to heat your home: Ready.gov is explicit that this raises the risk of carbon monoxide poisoning, fire and burns. Install carbon monoxide detectors with battery backup on every level of your home and test them monthly. If a detector sounds, or anyone develops a headache, dizziness, nausea or confusion, get everyone outside into fresh air at once and call emergency services — 911 in the US and 999 in the UK.
What to do during the outage
Work through a short sequence. First, check whether it is a power cut or a problem in your home: see if neighbours lost power or streetlights are out, and check your fuse box or breaker panel. In the UK, report it to your local network — the Energy Networks Association postcode tool tells you who your operator is — and the power cut helpline is 105. In the US, report the outage to your electricity provider and sign up for text alerts if offered. Second, turn off or disconnect appliances: power may return with surges that cause damage, so unplug televisions and computers and turn heating thermostats down. Leave one light on inside and one outside, so you and repair crews know when power returns. Third, keep the fridge and freezer closed, and use flashlights rather than candles. Listen to a battery-powered radio for official advice, and keep your phone charged with a power bank for essential calls only. If heat or cold is extreme, go to a community location with power, such as a library. Check on neighbours, especially older people, people living alone and anyone depending on powered medical equipment.
Staying warm, connected and calm
Cold creeps up quietly. Layer clothing, wear a hat indoors, and gather the household in one room, closing doors to the rest of the house to keep warmth in. Blankets, sleeping bags and extra layers matter more than a single heavy coat. Seal gaps around windows and doors with towels to hold the heat. Never bring a barbecue, patio heater or camping stove indoors, and never leave a portable heater unattended. If the house is getting dangerously cold, or anyone shows signs of hypothermia — shivering that stops, confusion, slurred speech or drowsiness — get to a warm place and seek medical help. Sign up for local alerts before an outage and keep a battery-powered radio. For children, keep books, games and snacks in the kit. For pets, prepare a kit with food, water and medication, and keep them indoors and warm.
When the power comes back
The return of power is not the end of the job. Wait a few minutes before switching everything back on, and check for damage: frayed wires, the smell of burning, or water where it should not be. If anything seems wrong, turn off the main breaker and call an electrician. Throw out refrigerated food above 40°F for four hours or more. Check frozen food — if it still contains ice crystals it may be safe to refreeze, but if it has thawed completely and feels warm, discard it. Check refrigerated medicines against their labels. Restock the kit the same day: replace used batteries, recharge the power bank, replace food and water used, and note anything missing. Then check on neighbours again, especially anyone who struggled.
A one-evening checklist
You can be ready in a single evening, for very little money. One: put a torch and spare batteries where every household member can find them in the dark. Two: fill bottles with water and put them in the freezer, and check you have three days of food that needs no cooking, plus a manual can opener. Three: charge a portable phone charger and write emergency contacts on paper. Four: test the carbon monoxide detectors on every level, and buy them if you do not have them. Five: write the household plan on one page and stick it on the fridge.
Sources
- Ready.gov — Power Outages (fridge about 4 hours, full freezer about 48 hours; generators outdoors only, at least 20 feet from windows; never heat home with a gas stove; CO detectors with battery backup on every level): https://www.ready.gov/power-outages
- Ready.gov — Build a Kit (water, non-perishable food, flashlight, battery or hand-crank radio, first aid kit, manual can opener, phone chargers and backup battery): https://www.ready.gov/kit
- American Red Cross — Power Outage Safety (food and water for at least two weeks; flashlights, not candles; CO detectors on each level; fuel tank at least half full): https://www.redcross.org/get-help/how-to-prepare-for-emergencies/types-of-emergencies/power-outage.html
- Canadian Red Cross — Power Outages (at least three days of supplies; fridge about 4 hours, freezer 24 to 36 hours; never use generators or barbecues indoors): https://redcross.ca/how-we-help/emergencies-and-disasters-in-canada/types-of-emergencies/power-outages
- British Red Cross — How to prepare for a power cut (updated 9 Nov 2026; three days of water and ready-to-eat food; torch and battery radio; helpline 105): https://www.redcross.org.uk/get-help/prepare-for-emergencies/power-cut