How to calculate your restaurant's food waste cost

By the Par Sheet team · October 3, 2026

Most kitchens know they throw food away. Fewer know what it costs, because the cost is spread across a hundred small decisions: a tray of prepped vegetables that did not sell, a case that went past its date, a plate sent back. This guide shows two ways to get a number, one quick estimate and one measured figure, and how to read the result.

Start with the quick estimate

The simplest version needs two numbers: what you spend on food in a month, and the share of it that is wasted.

Monthly waste cost = monthly food purchases × waste share

Here is an example with made-up numbers: a restaurant that buys $19,200 of food a month and wastes 6% of it loses $1,152 a month, or $13,824 a year.

The hard part is the waste share, because most kitchens do not know theirs. There is no single published percentage that fits every concept and menu, so treat any guess as a placeholder. A review of earlier studies in the International Journal of Applied Management and Technology reports that 4% to 10% of the food restaurants buy never reaches the customer [1]. The EPA, as quoted by Los Angeles County Public Works, puts the top of the range at up to 10% of food purchased by commercial businesses [2]. Use that as a range to test, not a prediction: your own number could sit outside it. Replace it with a measured figure as soon as you have one.

Then measure the real figure

An estimate is a good reason to start measuring, but a measured number is the one worth acting on. You need three things.

1. A record of what you throw out. Every time something goes in the bin, write down the item, how much, and why. The reason matters as much as the amount, because "expired," "overproduced," "dropped" and "returned by the guest" have different fixes.
2. A cost for each item. Use what you actually paid per unit on your latest invoice, and multiply by the amount discarded. A tray of 3 lb of sliced peppers at $2.50 a pound is $7.50.
3. A denominator. Divide the month's waste cost by what you received in that month. That gives you the waste share in the formula above, from your own numbers.

You do not need to be perfect. A log that captures most of the waste, kept every day, tells you more than a perfect log kept for one week.

Find where it comes from

When you add up a month of entries, sort them by reason and by item. In most kitchens a few items and one or two reasons account for most of the dollars. That is where to start. If expired product is the biggest line, look at your par levels and ordering. If overproduction leads, look at prep quantities. The fix follows from the reason you recorded.

Also decide whether to count plate waste, the food guests leave on the plate. It is a different problem from kitchen waste, with different fixes such as portion sizes. ReFED, a nonprofit that tracks food waste in the US, estimates that restaurants and foodservice businesses generated 12.5 million tons of surplus food in 2024, and that nearly 70% of it was plate waste [3]. That figure covers the whole sector, not your kitchen, but it is a reason to log plate waste as its own reason rather than lumping it in with prep and spoilage.

How this connects to food cost

Waste is one piece of your overall food cost percentage, which is the cost of food used divided by food sales. The usual formula is (beginning inventory + purchases − ending inventory) ÷ food sales [4]. With a beginning inventory of $16,000, purchases of $4,000, an ending inventory of $17,000 and food sales of $10,000, that works out to 30% [4]. That example also shows a useful distinction: your actual food cost includes waste and theft, while an ideal cost is calculated from recipes. The gap between the two is the part to investigate [4]. The National Restaurant Association's figures, as reported by DoorDash, put the median food cost at 32.0% of sales for full-service restaurants and 32.4% for limited-service restaurants in 2024 [5]. Your own number may be higher or lower depending on menu and concept. What matters is that food thrown out is food you paid for and never sold, so every dollar of waste you remove goes straight to the margin rather than to a menu price.

Does measuring actually reduce waste?

There is some evidence that it does. Champions 12.3, a coalition working on food loss and waste, studied 114 restaurants in 12 countries and found that food waste fell by 26% on average in the first year of efforts to reduce it [6]. That study covers restaurants that took deliberate action to reduce waste, which usually starts with measuring it. It does not promise that any particular kitchen will see the same drop.

A simple routine to start this week

• Put a sheet or a tablet by the bin and decide the five reasons you will record.
• Log everything for two weeks, before you change anything.
• Cost the log from your latest invoices.
• Divide by what you received in the same two weeks.
• Pick the single biggest line and change one thing about it.