Pagham Harbour
| Site of Special Scientific Interest | |
| Location | West Sussex |
|---|---|
| Grid reference | SZ 872 968 |
| Interest | Biological Geological |
| Area | 629.0 hectares (1,554 acres) |
| Notification | 1986 |
| Location map | Department for Environment, Food and Rural Affairs map |
Pagham Harbour is a 629-hectare (1,550-acre) biological and geological Site of Special Scientific Interest on the western outskirts of Bognor Regis in West Sussex. It is a Geological Conservation Review site, a Nature Conservation Review site, a Ramsar site, a Special Protection Area and a Marine Conservation Zone. An area of 599.1 hectares (1,480 acres) is a RSPB Local Nature Reserve.
Land owners of the harbour include the Royal Society for the Protection of Birds, the Crown Estate and the Church Commissioners.
The harbour forms an area of saltmarsh and shallow lagoons. It is not an estuary, as no major streams enter the harbour with the only freshwater inflow a few small streams draining surrounding fields.