How Long Unopened Coffee Stays Fresh For

If you're the type to stock up on your favorite single-origin coffee for the perfect pour-over brew, you've probably asked yourself how long unopened coffee stays fresh. The answer depends on a few key factors: whether the coffee is ground or whole bean, how it's packaged, and how it's stored. Similar to the reason why whole spices are better than ground, coffee beans stay fresh way longer than ground coffee. That's because grinding coffee increases its surface area and exposes the aromatic oils and compounds to oxygen, which accelerates the breakdown of flavor and aroma. 

The kind of packaging your beans or grounds come in plays a big role in freshness. Vacuum-sealed bags remove air from the package, slowing oxidation. These are common in grocery-store brands and can keep coffee fresh for many months. Nitrogen-flushed bags replace the tiny bit of oxygen that remains after vacuum sealing with nitrogen. This is standard in many specialty roasters and is particularly effective for preserving aroma and flavor. Tin-tie bags or paper bags without proper sealing let in oxygen and moisture, so they're best for short-term use only — even if unopened.

Unopened whole coffee beans in a vacuum-packed or nitrogen-flushed bag will last between six and nine months after the roast date. If the beans are in a standard, foil-lined bag with a degassing valve, they'll stay fresh for up to four months. Even in the best-quality packaging, unopened ground coffee in a vacuum-sealed or nitrogen-flushed bag will only last around five months. If it's just standard grocery store packaging, you'll maybe have closer to three months.

Once opened, all bets are off; coffee begins to degrade quickly after contact with air, especially if it's ground. Even if your coffee is within the typical window of freshness, it still may have lost flavor, especially if stored in a warm or humid area. Coffee doesn't spoil like milk, but stale coffee loses aroma, complexity, and depth. To check if your unopened coffee is still fresh, you've got a couple options. 

First, smell it after opening. If it lacks that strong, rich coffee aroma, it's likely stale. If you're still in doubt, just brew a cup. If the flavor is weak, dull, or papery, your coffee is probably past its prime.

To keep coffee fresh, avoid oxygen, light, heat, and dampness. Don't store it near the stove, sunny windows, or anywhere near moisture. Buy whole beans whenever possible and grind only what you need, when you need it — always using a burr grinder, of course. If you want a rich, satisfying brew every time (who doesn't?), keep an eye on roast dates, choose airtight packaging, and when in doubt, always go for the whole bean.