Lemon is the citrus fruit commonly served with paella to add freshness.
Lemon is usually offered in wedges alongside the finished dish, allowing diners to squeeze a small amount of juice over their portion. Its sharp acidity contrasts with the savory rice, olive oil, stock, saffron, and browned ingredients. The lemon is generally added after cooking, not simmered in the paella.
The custom is especially associated with seafood paella and international restaurant service, although it is not a required ingredient in traditional paella valenciana. Valencian cooks and food purists sometimes object to lemon because its acidity can mask the flavor of a carefully balanced broth and saffron. In other households, however, it remains a familiar garnish or personal preference.
Lemon should not be confused with lime, which is more common in some Latin American and tropical cuisines. Orange is important to Valencia as a regional citrus fruit, but it is not the standard citrus garnish for paella. The practical rule is simple: serve lemon separately and let each diner decide.