Seagate or Sea Gate may refer to:
- Seagate Technology, a manufacturer of computer hard disks
- Sea Gate, Brooklyn, a community in Brooklyn, New York City, USA
- East Coast Seagate Distribution, a (now defunct) comic book distributor named after the Brooklyn community
- Seagate, North Carolina, a community in North Carolina, USA
- One SeaGate, the tallest building in Toledo, Ohio
- SeaGate Convention Centre in Toledo, Ohio
- Seagate bus station, in Scotland
- Seagate, a historic estate built in Florida in 1929 by Gwendolyn and Powel Crosley
- Friends of Seagate, a 501(c)(3) nonprofit preservation organization formed in Florida
- Sea gate, a channel or waterway which gives access to the ocean
- A Sea-gate on a ferry