I've tasted coffee roasted two weeks ago and coffee roasted six months ago, side by side. The difference isn't subtle. The fresh stuff has aroma, brightness, and a clean finish. The old stuff is flat, woody, and sometimes bitter. Roast date is the single best predictor of that experience.

But here's the nuance: roast date isn't everything. Storage matters. If a roaster stores beans in a cool, dark place, they degrade slower. Packaging matters too—a bag with a one-way valve and a nitrogen flush can keep beans fresher longer. And grind size matters: if you buy pre-ground, you're already behind. Buy whole beans and grind at home, and you'll get more life out of any roast date.

So, if you see two bags of coffee, one with a roast date three weeks ago and one with a best-by date next year but no roast date, which do you choose? The one with the recent roast date, every time.