All coffee guides · Espresso Technique
The filter basket is the small stainless steel cup inside your portafilter that holds the coffee grounds. It is often overlooked, but basket size and quality directly affect extraction evenness, resistance to channeling, and the range of doses you can work with. Understanding your options helps you get consistent results and know when a basket upgrade is worthwhile.
Single baskets are designed for around 7-9g of coffee, producing a single espresso of roughly 25-30ml. They are rarely used in home setups because they have a narrow dose window, are prone to channeling, and most home machines have 58mm group heads better suited to double baskets. Single baskets are more common in commercial settings where a straight single shot is needed for a specific recipe.
The double basket is the standard for home espresso. Most 58mm portafilters ship with a 14-18g double basket, and this is where the vast majority of home baristas operate. Double baskets give you enough coffee depth that water flows through evenly, and the dose range (typically 14-20g depending on basket capacity) is wide enough to work across different coffees and grind settings.
Triple baskets hold 20-24g and are used when you want a larger dose for longer extractions or a higher-volume shot. They require a more forceful machine pump to maintain pressure through the larger puck. Increasingly popular in specialty settings, they can produce outstanding results but are less tolerant of uneven distribution — the larger surface area amplifies any inconsistency in how the grounds are prepared.
Precision baskets (made by manufacturers like IMS, VST and Pullman) are machined to much tighter tolerances than stock OEM baskets. The holes are more uniform in size and placement, the walls are more consistent, and ridgeless designs allow the puck to release cleanly. The improvement in extraction evenness is real and measurable — particularly for reducing channeling. Most experienced home baristas consider a precision basket one of the highest-value upgrades available, typically costing £20-50.
Most stock baskets have a ridge around the inside — a small groove that locks the basket into the portafilter. Ridgeless baskets have no ridge and sit flat-sided all the way to the top, making puck release cleaner and easier to inspect. They require a portafilter with a spring clip or compatible design to hold them in place. Most precision baskets are ridgeless. If your portafilter does not have a spring clip, check compatibility before buying a ridgeless basket.
Browse all 98 coffee guides or start a free espresso journal on Baristalog.