There’s no single answer because expiration timelines vary widely by product type. Canned food typically lasts 2 to 5 years after its manufacture date, medications retain potency for at least 1 to 5 years, cosmetics range from a few months to 3 years, and batteries hold a charge for 5 to 15 years. The manufacture date (often printed as “MFG”) tells you when the product was made, but what matters is the type of product, how it’s stored, and whether the container has been opened.
Why the MFG Date Isn’t an Expiration Date
The manufacture date is simply a timestamp for when the product was produced. It doesn’t tell you when the product becomes unsafe or ineffective. That gap between manufacture and expiration is determined by the manufacturer through stability testing, where products are exposed to elevated heat and humidity to simulate long-term aging. The speed at which a product degrades under stress lets manufacturers calculate how long it will last under normal storage conditions. Each product has a different degradation rate depending on its chemistry, packaging, and ingredients.
In the United States, there are almost no federal laws requiring expiration dates on consumer products. Infant formula is the notable exception: the FDA requires a “Use By” date on every container, and the manufacturer guarantees nutrient content and quality only until that date. For nearly everything else, date labels are voluntary and often misunderstood.
What Date Labels Actually Mean
If your product has a date label, the wording matters more than the date itself. A “Best if Used By” date indicates when a product will be at its best flavor or quality. It is not a safety date. A “Sell-By” date is for store inventory management, telling retailers how long to display the product. It’s also not a safety date. A “Use-By” date marks the last day recommended for peak quality, but even this isn’t a safety cutoff (except for infant formula).
Some products only show a manufacture date or a cryptic can code. These codes appear as a series of letters and numbers referring to the date the product was canned or produced. If you see something like “23015,” the first two digits often represent the year (2023) and the remaining digits are the batch number. A printed “MFG 01/23” simply means the product was manufactured in January 2023.
Food: 2 to 5 Years for Canned Goods
Commercially canned foods generally retain their best quality for 2 to 5 years from the manufacture date. High-acid foods like tomatoes, citrus fruits, and pickled items sit on the shorter end of that range because acid gradually degrades flavor and texture. Low-acid foods like beans, meat, and vegetables tend to last longer.
Safety is a different question from quality. Canned foods in intact metal or glass containers remain safe to eat well beyond that 2-to-5-year window, as long as the seal hasn’t been broken, the can isn’t bulging, and it’s been stored in a cool, dry place. The taste and nutritional value will decline over time, but the food won’t necessarily make you sick. Once you open a can, the contents last between one day and one week in the refrigerator depending on the food.
Dry pantry staples like pasta, rice, and dried beans follow different timelines. White rice and dried pasta can last 1 to 2 years past manufacture if kept sealed and dry. Oils and nut-based products go rancid faster, often within 6 to 12 months of manufacture even when unopened, because fats oxidize over time.
Medications: Often Good Well Beyond the Label
Most over-the-counter and prescription medications carry expiration dates set 1 to 5 years after manufacture. These dates represent the last point at which the manufacturer guarantees full potency, but the real shelf life is often much longer. A large-scale study found that over 90% of more than 100 tested drugs, both prescription and over-the-counter, were perfectly good to use even 15 years after their expiration date. Ongoing research confirms that many drugs retain at least 90% of their potency for five or more years past the labeled expiration when stored properly.
The FDA runs a Shelf Life Extension Program (SLEP) that tests medications in national emergency stockpiles and routinely extends their shelf lives beyond the printed date once they pass testing for safety, strength, and purity. This program saves significant money by reducing the need to replace stockpiled medications that are still effective. However, not every drug ages equally. During one round of SLEP testing, inspectors found signs of moisture and unknown impurities in certain injectable medications, which is why proper storage matters enormously. Heat, humidity, and direct sunlight accelerate degradation.
Liquid medications and anything requiring precise dosing (like insulin or nitroglycerin) are less forgiving than solid tablets. If a medication has changed color, has a strong odor, or appears crumbled, it’s best to replace it regardless of the date on the label.
Cosmetics and Skincare: No Legal Requirements
There are no U.S. laws requiring cosmetics to have expiration dates on their labels. Manufacturers are responsible for making sure their products are safe, and the FDA considers determining shelf life part of that responsibility, but it’s not enforced through mandatory labeling. Most unopened cosmetics last 1 to 3 years from manufacture depending on the formulation and preservatives used.
The bigger concern is what happens after you open the product. Dipping fingers into creams and lotions introduces bacteria and fungi that preservatives can only hold off for so long. Over time, those preservatives break down, and microbial growth becomes a real issue. Eye-area cosmetics have shorter safe-use windows than other products because eye infections can be serious. Mascara, for example, should typically be replaced 2 to 4 months after you first open it.
Sunscreen and acne treatments are regulated as drugs, not cosmetics, which means they are required to have expiration dates on the label and must be tested for stability. If your sunscreen has passed its printed expiration date, it may no longer provide the SPF level on the bottle.
If a cosmetic product only shows a batch code and no clear date, look for a small open-jar icon on the packaging with a number like “12M” or “24M.” That tells you how many months the product remains good after opening. To figure out when it was made from a batch code, many online tools let you enter the brand and code to decode the manufacture date.
Batteries: 5 to 15 Years
Alkaline batteries hold their charge for 5 to 10 years from the manufacture date when stored at room temperature. Lithium primary batteries last even longer, maintaining charge for 10 to 15 years with minimal self-discharge. They also perform well in extreme temperatures, from -40°F to 122°F. Rechargeable batteries (nickel-metal hydride or lithium-ion) lose charge faster in storage, typically degrading noticeably within 3 to 5 years even if never used.
If you find old batteries with only a manufacture date, alkaline cells are likely fine for years after that date. You’ll notice declining performance gradually rather than a sudden failure. The best storage conditions are cool, dry, and away from metal objects that could cause a short circuit.
How Storage Changes Everything
Across every product category, storage conditions matter as much as time. Heat is the single biggest factor that accelerates degradation, whether you’re talking about food, drugs, or batteries. Humidity is the second. A canned good stored in a cool basement will outlast the same product kept in a hot garage by years. Medications stored in a bathroom cabinet, where heat and steam fluctuate daily, degrade faster than those kept in a dry, temperature-stable spot.
If your product has only a manufacture date and no expiration date, use the general timelines above as a starting point, then adjust based on how it’s been stored. A product kept in ideal conditions will almost always last longer than its labeled shelf life suggests. One that’s been left in a car trunk during summer or stored near a heat source could fail well before any printed date.