How fresh do coffee beans need to be for espresso?

For espresso, beans are best between 7 and 21 days post-roast. Before 7 days, beans are still off-gassing CO2 from the roast, which causes uneven extraction and excessive crema. After 3–4 weeks, staleness reduces sweetness and body. Buy beans in small quantities (250–500g) from local roasters or online roasters that ship fresh-roasted. Whole beans stay fresh longer than pre-ground — invest in a grinder and grind per shot.