How long do leftovers last? Plan them into the week

"Cook once, eat twice" means one big pot, two or three meals and a shorter grocery list. It also has a clock attached. The question isn't only how long leftovers last; it's whether the days you planned to eat them fall inside that time. Here is the federal guidance, and a planned week checked against it day by day.

The rules, from FSIS and FoodSafety.gov

The two federal pages give different freezer times for cooked meat: FSIS says 3 to 4 months, the FoodSafety.gov chart 2 to 6 months. FoodSafety.gov makes the condition explicit: food kept continuously frozen at 0 °F (−18 °C) or below can be kept indefinitely; the freezer times in its chart concern quality. Freezing does not make improperly handled food safe. Use the shorter listed quality period if you prefer a conservative plan.

A cook-once week, checked day by day

Our "cook once, eat twice" example plans 12 meals from 5 recipes. Four are planned more than once: the yogurt breakfast (not cooked, so it doesn't count here), the roast chicken, the chili and the noodle soup. The chart counts days from cooking day.

• Chili: cook an 8-serving batch Tuesday, serve 4 that evening and eat the reserved portions again Wednesday (+1) and Friday (+3). The planned dates fall inside the window if the food is handled and stored appropriately; the planned servings add up to exactly one 8-serving batch (4 + 2 + 2 = 8).
• Roast chicken: cooked twice, Monday and Saturday, and eaten the same day both times.
• Noodle soup: eaten Tuesday, Wednesday and Sunday. One pot kept from Tuesday to Sunday would be 5 days old, past the 3-to-4-day limit. To use these dates without keeping one pot refrigerated for five days, cook twice: a full pot on Tuesday, a half pot on Sunday. The other option is to freeze Sunday's portion on Tuesday.

The shopping amount supports two cooking sessions; it does not schedule them

The soup recipe serves 4. The week plans it for 2 on Tuesday, 2 on Wednesday, 2 on Sunday: 6 servings, one and a half recipes. The grocery list multiplies by 6 ÷ 4 = 1.5, so it already contains the ingredients for a full pot on Tuesday (eaten Tuesday and Wednesday) and a half pot on Sunday. The planner sums these servings; it does not record when a batch was cooked, monitor storage temperatures or flag unsafe repeats. Cooking twice is a manual decision in this example, not an automatic safety check.

How to plan leftovers that stay inside the window

1. Plan the repeat within 3 days of cooking day. Cook on Sunday, eat again by Wednesday. That keeps you at the short end of the 3 to 4 days.
2. Set the servings on each repeat. A lunch for 2 from a dinner for 4 is a smaller meal; giving it its own servings keeps the shopping amounts right.
3. Reserve and freeze later-week portions on cooking day. This is our conservative planning choice, not a claim that properly refrigerated food must never be frozen later. Follow handling and cooling guidance and keep frozen portions at 0 °F (−18 °C) or below; reheat leftovers to 165 °F.
4. Refrigerate within 2 hours. Within 2 hours of cooking, or 1 hour above 90 °F. FSIS advises dividing large amounts of food, such as a pot of chili, into shallow containers so they cool quickly.
5. Reheat soups to a boil. FSIS says to reheat sauces, soups and gravies by bringing them to a rolling boil.

The cook-once week also has the shortest grocery list of our three templates: 22 lines against 26 and 33. See the three templates side by side, or how the week compares with the USDA food budgets.