Why Do Wine Bottles Have a Dimple in the Bottom?

Wine bottles are elegant. Their sloped necks come to a gentle peak. They’re supported by a stout but understated trunk of a bottle. The color, typically rich sap green, absorbs color and emits a warm glow in the light of a kitchen or bar. The bottles themselves are sometimes as much a work of art as the wine that’s inside them.

But there’s one bit of the typical wine bottle that remains elusive: the bottom. The “dimple” or bulge at the bottom of many wine bottles is known as the “punt,” and it’s not entirely clear why it exists.

Wine bottles have had punts as long as the earth has had wine bottles, it seems, and until we have the capability to time travel, we’re left to wonder how the tradition of wine punts started and, perhaps more importantly, why we still do it today.

No, most punts are so small you’re not losing a single teaspoon. Some, yes, are more pronounced, but if this were really used as a cost-saving measure, you could bet most bottles would have exaggerated punts to make a good season’s wine supply stretch a bit more.

If you do a quick Google search on the theories behind wine bottle punts, you’ll quickly stumble across speculation that suggests higher quality wines have bigger punts because the bottle is more stout and sturdy. (More glass is needed for the longer punt, the theory goes, and wealthy winemakers can afford the more expensive bottles.) That’s just simply not true. A punt will tell you as much about the quality and taste of wine as the label will. That is to say, very little.

This holds some merit. Punts increase surface area, so bottles in fridges or buckets of water might cool faster. But this theory is busted when you realize punts have been present on wine bottles long before anyone had heard of coolant for a refrigerator, or even ice for that matter. So while it may help get your whites crisp and cool today, that’s not why punts exist.

They actually do, but that’s not likely the reason they’re there. Sediment forms at the bottom of bottles as wine sits and ages. If you decant the wine, the sediment may remain in the valleys between the punt and bottle wall. That can help with flavor.

However, there’s no guarantee the sediment stays in place. It’s a happy byproduct of the punt’s existence, but it doesn’t seem that’s why punts were used in the first place.

Truthfully, beats us. The best theory seems to be that wine bottle makers of yore needed a way to make sure their bottles stood flat on a table. The bottoms of hand-blown bottles may round out slightly as they cool. They may even have a sharp point because of the tools the glassblower uses. To keep this from happening (and bottles of wine from teeter-tottering off the table), glassblowers could have pushed up ever so slightly to create what we know today as the punt.

Now that most wine bottles are made by machine and are far sturdier than bottles made decades and centuries ago, the punt isn’t perhaps necessary. Instead, it seems to be a vestige of bygone days.