What does "Filter Roast" mean?

A filter roast is a coffee roasting style specifically designed for brewing methods like pourover (V60, Chemex), or drip machines. These are brewing methods that mostly don't use the high pressure and heat of espresso brewing.

Beans roasted for filter are roasted at lower temperatures for a shorter time. This approach preserves the bean’s natural acidity, aroma, and unique origin flavors, resulting in a lighter, clearer, and more delicate cup.

Filter roasts are prized for highlighting the subtle characteristics of the coffee’s origin, such as fruity or floral notes, and are best enjoyed without milk to fully appreciate their complexity.

In contrast, an espresso roast is roasted longer and at higher temperatures to develop a richer, fuller body and to increase the solubility of the coffee grounds. This is important for the short, high-pressure extraction of espresso machines. This process reduces acidity and brings out bolder, more intense flavors, often with notes of chocolate, nuts, or caramel, and a heavier mouthfeel.

While espresso roasts can be brewed as filter coffee, they tend to taste more robust and less nuanced; brewing a filter roast as espresso, on the other hand, often results in a sharp, sour shot as the filter roast doesn't reduce accidity to the same extent as espresso.

So when you're staring at a range of coffee, you can immediately ....filter.... your options by focussing on the coffee that's going to match how you're brewing. 

Of course, there's no rules around any of this. The specialty coffee industry has developed some norms, including the above, based on best efforts to deliver the best coffee possible. What that looks like for different groups of people is subjective, and constantly changing. 

You do you, we won't call the cops.