For many supplements, the date on the label is about potency, not safety. A bottle a little past that date may just be weaker than it was. Whether you should still take it depends more on how it was stored and what it looks and smells like now than on the calendar.
What the date really means
The maker is telling you how long the product should stay at full strength. Go a bit past that and you may simply be getting less of what's on the label.
Storage changes the math. Heat, humidity, and light break supplements down faster, so a bottle that lives in a steamy bathroom may not make it to its printed date at all. A pantry shelf or a bedroom drawer is kinder to it than a windowsill or the top of the microwave.
Different forms also age differently. Tablets and hard capsules usually hold up longer than soft-gels, powders, or liquids, which are more sensitive to air and moisture once the seal is broken. Gummies left somewhere warm can dry out or get a strange texture well before the date.
When to just replace it
If it smells rancid, has changed color, or the texture looks wrong, replace it. You gain nothing by taking something that has clearly degraded.
Before you take anything from an older bottle, look for capsules stuck together in a clump, tablets that crumble or feel soft, powder that has caked from moisture, or a smell that's sharper or more chemical than you remember. None of these means it will hurt you. But if it doesn't look or smell the way it did when you opened it, a new bottle is the less stressful choice.
Not sure about a specific product, especially fish oil, probiotics, or a liquid vitamin? Ask your pharmacist. That's usually quicker and more reassuring than digging around online.
Building habits that make this less of a guessing game
Expired bottles usually have the same backstory. One gets pushed to the back of a shelf, sits there for a few months, and turns up later. If you take your supplements at about the same time every day, tied to brushing your teeth or making coffee, bottles get used up steadily instead of being forgotten.
For anything you're trying for the first time, a smaller bottle makes sense. If it doesn't stick in your routine, you won't have months of pills slowly aging in the cabinet.
Some people take several supplements at once because it's convenient. If you take more than one or two regularly, ask a pharmacist whether any of them should be spaced apart, from each other or from coffee and other drinks.
Knowing what you have and using it consistently means less of it expires. Pillog helps you keep that routine on your phone with no account, so a bottle in the cabinet is much less likely to outlast its usefulness.