Do I need a best-by date or lot code on jam, and how do I choose one?

Federal rules do not require a date on jam. Infant formula is the only food with a federally required date [1]. Neither do they require a lot code on standard fruit jam, though buyers and some state programs ask for one, and you need some way to find a batch if a problem turns up. Put both on anyway. A best-by date tells customers when the jam is at its best, and a lot code lets you pull one batch instead of everything. This page shows how to set a best-by date you can defend from published storage guidance, how to build a lot code that is more than a date, and what to do with jars that age on your shelf.

What a date on jam means, and what it doesn't

The U.S. Department of Agriculture's food safety agency puts it plainly: "Except for infant formula, product dating is not required by Federal regulations" [1]. Where dates appear, they describe quality: "Dates are not an indicator of the product's safety" [1]. The agency recommends that manufacturers who date their products use the phrase "Best if Used By," to reduce confusion and waste [1].

That framing fits jam well. A properly processed, sealed jar of full-sugar jam does not become unsafe on a particular day. It slowly loses color, flavor and texture. A best-by date is your promise about quality, and it is the date you should be willing to stand behind if a customer opens a jar the week before it.

Check your state, too. Some cottage programs and markets have their own date expectations. Your state's page in selling jam in your state notes any label requirements found.

Setting a best-by date you can defend

You do not need a lab study to set a reasonable date for a standard product. You need published guidance, honest storage, and your own observations.

Step 1: start from the published storage guidance

The National Center for Home Food Preservation recommends using home-canned jams and jellies within a year for best quality, stored in a cool, dark, dry place at 50 to 70°F [2]. It also notes that color, flavor and texture change over time, that lighter-colored jams may darken faster, and that reduced-sugar products may decline sooner [2]. Once opened, regular cooked jam keeps best for about a month refrigerated at 40°F or below; reduced- and no-sugar spreads typically keep for less [2].

Step 2: adjust for your product

No published source gives a shelf-life number for reduced-sugar spreads; NCHFP says only that they decline sooner [2]. If someone offers you a precise figure, ask where it came from.

Step 3: keep retained samples and check them

Set aside two or three jars from every batch, stored where your stock is stored. At regular intervals (every three months suits most makers), open one, and note its color against a fresh jar, its flavor, its set, and any weeping or darkening at the top. Write the observations on the batch record. After a season, you will know whether your peach jam holds its color for ten months or six, and you can set the best-by from your own evidence rather than a guess. The batch log template has space for these checks.

Step 4: print it plainly

Use the agency's recommended phrase and an unambiguous date: "Best if used by 07/2027" or "Best if used by July 2027." Avoid formats such as 07/08/27 that a customer can read two ways. Put it where it will not be torn off when the jar opens, such as the lid or the back label.

Lot codes that are more than a date

A lot code identifies the batch a jar came from. The USDA food safety agency describes these "closed" codes on shelf-stable foods as the manufacturer's tool to "rotate their stock and locate their products in the event of a recall," and says they are not meant to be read as a best-by date [1].

The commonest mistake is to use the production date as the lot code. It fails in three ways:

1. Two batches on one day share a code. If the second batch of strawberry had a seal problem, you cannot tell its jars from the first batch's.
2. Customers read it as a date. "07152026" on a lid looks like an expiry, and people throw out good jam or keep stale jam.
3. It carries no product information. If strawberry and apricot were both made on July 15, the code does not tell them apart.

A simple scheme that works

Build the code from four parts: product, year, day of the year, batch of the day.

The code is short enough to hand-write or stamp, readable by you, and unlikely to be mistaken for a date. The batch sheet for ST26196-2 then holds everything about that batch: fruit source and its lot, pectin lot, lid lot, weights, set test, refractometer reading, processing time, yield and seal failures. If a customer calls about a jar, you read the code and pull the sheet. The full record system, including distribution records and mock recalls, is on records, lot tracing and recalls.

Some states require batch numbers for particular products. Texas, for example, requires a batch number on the label of pickled, fermented or acidified cottage foods [3]. If you make pepper jelly, check whether your state treats it as one of those; see pepper jelly.

What to do when stock ages

Jam that sits through a slow winter is a normal part of the business. Handle it in this order:

1. Rotate. Sell oldest first. Arrange the market table and storage shelf so the earliest lot is in front.
2. Inspect before every market. Check lids for bulging or loss of vacuum, look for leaks, mold, rising bubbles or fermentation. Any jar with signs of spoilage is discarded, never sold; NCHFP advises discarding all the contents of a jar that shows mold or other spoilage [2]. How to recognize and dispose of a bad jar safely is on how to tell a jar has gone bad.
3. Pull jars at their best-by date. FSIS treats dates as quality dates [1], so a sealed jar past its date is usually still safe, but you promised the customer quality. Take it off the table.
4. Do not relabel with a new date. A later best-by on an old lot misleads the buyer. If you want to sell older stock, ask your state program whether a clearly marked discount for jars past their date is acceptable; rules and market policies vary.
5. Use what you pull. Older jars make good baking stock, samples for your own tasting, or household use, as long as they are sound.
6. Learn from it. If a flavor routinely ages on the shelf, make smaller batches of it, or move it to the season it sells. Darkening in storage has its own causes and fixes, covered on jam that darkened or lost flavor.

Keep the records that make the codes useful

A lot code is only as useful as the batch record behind it. The record-keeping page sets out what to capture for each lot, how long to keep it and how to run a practice recall: records, lot tracing and recalls. For the storage conditions that make your best-by date hold up, see storing jam and how long it keeps.

References

1. USDA Food Safety and Inspection Service, Food Product Dating, not dated (viewed October 2026). https://www.fsis.usda.gov/food-safety/safe-food-handling-and-preparation/food-safety-basics/food-product-dating
2. National Center for Home Food Preservation, Storing Home Canned Jams and Jellies, October 2005. https://nchfp.uga.edu/how/make-jam-jelly/jams-jellies-general-information/storing-home-canned-jams-and-jellies/
3. Texas Department of State Health Services, Texas Cottage Food Production, not dated (2025 rules). https://www.dshs.texas.gov/retail-food-establishments/permits-retail-food-establishments/texas-cottage-food-production