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.

At the time of its listing on the National Register of Historic Places in 1986, it was the last Pilgrim that was still flightworthy.