NGC 18 is a double star system located in the constellation of Pegasus.

[1] It was first recorded by Herman Schultz on 15 October 1866.

It was looked for but not found by Édouard Stephan on 2 October 1882.

It was independently observed by Guillaume Bigourdan in November 1886.

[1] Both stars are 2528±20 light-years away, and based on this distance have a minimum separation of approximately 2,700 astronomical units, an unusually wide separation for a binary system.