Although only one aircraft was completed, a modified version also known as the Pilgrim 100-A was in production for American Airways, the first operator of the type in 1931.

In 1932, the US Army Air Corps bought four Pilgrim Model 100-Bs designated the Y1C-24 and were initially assigned as light cargo transport and supply aircraft.

[1] After a short time in service, the Y1C-24s were adapted for use as aeromedical evacuation aircraft, carrying up to four litter patients.

Exploiting the Y1C-24's ability to take off and land in a relatively short distance, the Y1C-24s remained in service into the late 1930s when they were replaced by newer air ambulance aircraft.

[1] Pilgrim 100-B N709Y is one of a few surviving aircraft from the early days of aviation in the history of Alaska.