A cheap 72-hour emergency kit from Walmart or Target: what to buy on a budget

What a 72-hour kit needs

Ready.gov says that "after an emergency, you may need to survive on your own for several days." Its basic kit list is: water (one gallon per person per day for several days, for drinking and sanitation), at least a several-day supply of non-perishable food, a battery-powered or hand crank radio and a NOAA Weather Radio with tone alert, a flashlight, a first aid kit, extra batteries, a whistle, a dust mask, plastic sheeting, scissors and duct tape, moist towelettes, garbage bags and plastic ties, a wrench or pliers to turn off utilities, a manual can opener, local maps, and a cell phone with chargers and a backup battery.

The Red Cross list is similar and adds a 7-day supply of medications, a multi-purpose tool, copies of personal documents, family and emergency contact information, extra cash and an emergency blanket. The Red Cross suggests a 3-day supply for evacuation and a 2-week supply for home, and the CDC's water figure is also 3 days.

Start with what you already have

Ready.gov's low and no cost page says: "Build your emergency supply kit over time. Start with items you may already have in your home, like a flashlight, extra batteries, copies of important documents, water and non-perishable food." Before you shop, check for a flashlight, a phone charger and power bank, a can opener, pantry food, a first aid kit, blankets, and your medicines. You may find you already have several of these.

The same page says: "Look for deals at garage sales and thrift stores. You may find useful items like camping gear, tools, cookware and backpacks or luggage at a fraction of the retail price." It also suggests you "contact your local fire department. They may have programs that provide fire or carbon monoxide detectors."

Buy in this order

You do not have to buy everything in one trip. Ready.gov suggests picking up an extra item each time you shop. A sensible order, ours rather than an agency's, is to cover the items that matter most first:

• Week 1, water and food: 1 gallon per person per day for 3 days, and 3 days of ready-to-eat food you like (canned meats, fruits and vegetables, peanut butter, cereal, protein bars), plus a manual can opener
• Week 2, light and information: a flashlight for each person, extra batteries, and a battery or hand crank radio, ideally a NOAA Weather Radio
• Week 3, health: a first aid kit, your prescription and non-prescription medicines, glasses or contact lens solution, and hygiene items
• Week 4, the rest: a whistle, dust masks, duct tape, garbage bags, a blanket for each person, a copy of key documents, and some cash in small bills

Water: the one item not to skimp on

The CDC says: "Store at least 1 gallon of water per person, per day for 3 days. You can use this water during an emergency for drinking, cooking, brushing teeth, and other uses. Try to store a 2-week supply if possible." It also says "unopened, commercially bottled water is the safest and most reliable source of water in an emergency." It suggests more water for pregnant women, people who are sick, pets, and hot climates.

Bottled water or gallon jugs from a big-box store meet that. Ready.gov says water that has not been commercially bottled should be replaced every six months. If you fill your own containers, see how to make water safe and how much water to store.

What to skip

Pre-packed survival kits can be handy but are not required. Check what is inside against the lists above, and remember you will still need water and food you like. You also do not need gear for scenarios far from your own: a household in a tornado area and one in a flood area need different extras, and our state pages show FEMA's risk ratings for yours.

Everything that needs batteries needs spare batteries, so buy the size your flashlight and radio use. For safety, Ready.gov says: "Never use a gas stovetop or oven to heat your home." and "Generators and fuel should always be used outdoors and at least 20 feet away from windows, doors and attached garages."

Keep it up to date

Ready.gov says to keep canned food in a cool, dry place, to store boxed food in tightly closed plastic or metal containers, to replace expired items as needed, and to "re-think your needs every year and update your kit as your family's needs change." Put the kit where you can reach it, and tell everyone in the home where it is. Our emergency kit checklist covers the basics, and the kit builder sizes a kit for your household.