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Group Gasket
Rubber seal between the portafilter and the group head — the part that goes hard, leaks, and stops you from locking in straight.
Category: Espresso Machine — Groups & Brew Path
The rubber, silicone, or composite ring that seals the portafilter against the underside of the group head during brewing. Without the gasket, no pressure seal — and no espresso.
Why it matters — The group gasket is the single most commonly replaced espresso machine part. Gaskets harden, compress, and leak over 6–12 months of regular use — replacing one can transform a machine that feels tired.
Good to know
- Silicone gaskets last 2–3× longer than rubber and don't harden as quickly.
- Symptoms of a worn gasket: coffee leaking around the portafilter, difficulty locking the handle in firmly, or pressure not building properly.
Related: Group Gaskets