For sewing machines manufactured since about 1990, look for the model number on the handwheel side of the machine near the on/off switch or the electric cord receptacle.
We often are asked for sewing machine parts to fit a Singer F1234567. The problem is this long number. If your sewing machine does not have a model number, but has a serial number similar in. Originally it may have been hand operated. To figure out what year your Singer 15 is from, check out the serial number database from the International Sewing Machine Collectors' Society. According to this, my sewing machine is from 1923. According to this, my sewing machine is from 1923.
You will find the model number on the front panel of machines manufactured in the 1970s and 1980s.
Singer Sewing Machine Serial Numbers Value
Sewing machines manufactured in the 1960s usually have the model number on the machine's front panel above or below the stitch length controller.
Sewing Machine Serial Number Database
On machines manufactured before 1960 the model number is located on a small plate on the front of the machine.