10/31/51 *****transitional production run 221__ AK 74-79 ….. 10/14/53 *****transitional production run 221__ AL 68-73 ….. Many of them were based on a Singer class 15 machine, and are commonly known as "Singer Clones" - read a bit more about them here. If your sewing machine looks a lot like these machines but has an off brand name, chances are you have a generic or clone machine.The overall condition of your machine is one of the biggest factors in estimating a value. 08/19/47 *****transitional production run 221-1 AH 31-34 ….. 01/23/50 *****transitional production run 221-1 AJ 55-59 ….. Serial numbers for the years 1851 to 1870 are not available.Serial numbers on Singer sewing machines manufactured prior to 1900 are numbers only.
Or you can look at this brief history of BERNINA sewing machines at to see if you can find a similar model to yours.
This will reveal the year your machine was manufactured.
However, lists of serial numbers for machines produced from 1851-1870 are unavailable because the original serial number log books were lost, according to Singer.
The excellent online Singer identification guide from Sandman Collectibles is the current gold standard for identifying vintage Singer machines.
It asks you to check off a list of features seen on your machine, narrowing it down until you arrive at the model number.