If you poured a Stout and Porter into separate glasses, without looking at the cans they came from, there’s a good chance you wouldn’t be able to distinguish which was which. After all, both styles are on the darkest side of the beer color spectrum, and they even share many of the same aromas, flavors, and mouthfeel characteristics. 

The main reason is because the two popular dark beer styles have become pretty interwoven over the years. For the most part, it comes down to what the brewers want to call their dark creations. But, if you want to impress your friends with some nifty beer knowledge, here’s a little history about how Stouts and Porters originated and what actually defines each style. 

The Porter Came Before the Stout

Historically speaking, the Porter actually made its debut before the Stout did. The Porter first appeared in London during the 18th century, with early recipes calling for heavy amounts of hops and large quantities of brown malt (resulting in the dark color). The Porter was a fast hit, and it became the first style of beer brewed around the world.

Its popularity also prompted brewers to start experimenting. Heavier versions started appearing — with bigger booze and more dark malts replacing hop quantities. The Baltic Porter style also emerged when the Porter reached the Baltic Sea (still in the 1700s); while breweries like Florida’s Cycle and North Carolina’s Casita Brewing craft their own versions today, Baltic Porters stood out from the get-go for its Lager-style cold fermentation. 

Within several decades, the Stout had grown out of the Porter as a stronger or “stouter” version of the style. Even the first iterations of Guinness were referred to as an “Extra Porter” or “Stout Porter.” It wasn’t until the mid-1800s that the term “Stout” even began referring to body, flavor, and color instead of just its robust strength. 

What’s the Real Difference Between a Stout and a Porter?

The Beer Judge Certification Program (BJCP) defines a Stout overall as “a very dark, roasty, bitter, creamy ale,” while a Porter is “a substantial, malty dark ale with a complex and flavorful roasty character.” These days though, you could go brewery hopping and hear a variety of different explanations. 

Stouts and Porters have become so intertwined over the years in terms of brewing methods, body, and flavors. If anything, the lagering process of the Baltic Porter makes it one of the few truly defined versions of these styles today. That said, the only main difference between the Stout and Porter that most of the brewing community agrees on is the type of malt used. 

Porters call for primarily malted barley, which imparts sweeter, more “desserty” flavors. Stouts go with primarily unmalted, roasted barley, which results in richer, almost grainy flavors as well as coffee notes. That said, so many modern dark beers undergo barrel aging and/or contain other additions that give them flavors not traditional of their style. For example, Smog City’s Coffee Porter, with over 5 lbs of roasted coffee in each barrel.

At the end of the day, it’s up to the brewers to decide whether they want to call their beer a Stout or a Porter. 

Today’s Brewers Are Changing Stout vs. Porter Classification Even More!

The modern craft movement has seen unparalleled innovation in flavors, style crossovers, and new ingredients. If you get a regular beer delivery, chances are you’ve already had quite a few beers that could technically be classified as either a Stout or a Porter.

The Stout style today ranges from boozy barrel-aged renditions like Heathen Brewing’s Epitaph to sweet treats like 903 Brewing’s cake-flavored Down with the Pastryarchy Tiramisu Stout. The Porter side is also growing increasingly diverse, from Firestone Walker’s barrel-aged Cherry Barrel Blossom to Maui Brewing’s sweet Imperial Coconut Porter Dolce. 

With so much creativity in today’s craft beer world, the lines are likely to get blurred even further. And that’s okay, because it means beer drinkers can explore new flavorful frontiers!