Singer decoder
Singer stamped a serial number into the bed of every machine, and kept a register of the blocks those numbers were allotted in. This lookup runs against our own snapshot of that published register — over 9,000 dated blocks — and shows you the real block your number falls in: its first and last serial, the machine class, and the date it was allotted.
One box, three brands. Pick the brand, type the number exactly as you find it on the machine, and read the answer with the record it came from.
The date in the register is the date the block of numbers was allotted to the factory — the machines were then built from that block, usually within weeks or months. Collectors date machines by allotment year, and so do we, but the result always prints the allotment date itself so you can see exactly what the record says. A well-known wartime case shows why: one block allotted in 1939 is documented on a machine that was not sold until 1946.
The letters before the number are the factory series. Singer did not issue them in alphabetical order, and a worn prefix is the most common reason a lookup fails — find yours here first if the decoder cannot place your number.
| Prefix | Factory | Years in the register | Blocks |
|---|---|---|---|
| AA | Elizabethport, New Jersey | 1924–1926 | 135 |
| AB | Elizabethport, New Jersey | 1926–1928 | 151 |
| AC | Elizabethport, New Jersey | 1928–1930 | 167 |
| AD | Elizabethport, New Jersey | 1930–1935 | 291 |
| AE | Elizabethport, New Jersey | 1935–1938 | 202 |
| AF | Elizabethport, New Jersey | 1938–1941 | 237 |
| AG | Elizabethport, New Jersey | 1941–1947 | 268 |
| AH | Elizabethport, New Jersey | 1947–1948 | 112 |
| AJ | Elizabethport, New Jersey | 1948–1950 | 120 |
| AK | Elizabethport, New Jersey | 1950–1952 | 141 |
| AL | Elizabethport, New Jersey | 1952–1955 | 108 |
| AM | Elizabethport, New Jersey | 1955–1959 | 120 |
| AN | Elizabethport, New Jersey | 1959–1964 | 191 |
| AP | Elizabethport, New Jersey | 1964–1966 | 98 |
| AR | Elizabethport, New Jersey | 1967–1968 | 42 |
| AS | Elizabethport, New Jersey | 1968–1970 | 59 |
| AT | Elizabethport, New Jersey | 1971–1971 | 4 |
| B | Elizabethport, New Jersey | 1904–1910 | 219 |
| C | Wittenberge, Germany | slide-chart ranges | 0 |
| D | Elizabethport, New Jersey | 1908–1909 | 226 |
| EA | Kilbowie (Clydebank), Scotland | 1935–1937 | 95 |
| EB | Kilbowie (Clydebank), Scotland | 1937–1939 | 96 |
| EC | Kilbowie (Clydebank), Scotland | 1939–1940 | 107 |
| ED | Kilbowie (Clydebank), Scotland | 1941–1947 | 162 |
| EE | Kilbowie (Clydebank), Scotland | 1947–1949 | 79 |
| EF | Kilbowie (Clydebank), Scotland | 1949–1950 | 63 |
| EG | Kilbowie (Clydebank), Scotland | 1950–1951 | 69 |
| EH | Kilbowie (Clydebank), Scotland | 1951–1953 | 77 |
| EJ | Kilbowie (Clydebank), Scotland | 1953–1954 | 86 |
| EK | Kilbowie (Clydebank), Scotland | 1954–1956 | 97 |
| EL | Kilbowie (Clydebank), Scotland | 1956–1956 | 82 |
| EM | Kilbowie (Clydebank), Scotland | 1956–1957 | 74 |
| EN | Kilbowie (Clydebank), Scotland | 1958–1959 | 74 |
| EP | Kilbowie (Clydebank), Scotland | 1959–1960 | 79 |
| ER | Kilbowie (Clydebank), Scotland | 1960–1960 | 57 |
| ES | Kilbowie (Clydebank), Scotland | 1960–1961 | 91 |
| ET | Kilbowie (Clydebank), Scotland | 1961–1962 | 84 |
| EV | Kilbowie (Clydebank), Scotland | 1962–1964 | 92 |
| EW | Kilbowie (Clydebank), Scotland | 1960–1970 | 184 |
| EX | Kilbowie (Clydebank), Scotland | 1964–1965 | 57 |
| F | Kilbowie (Clydebank), Scotland | 1910–1920 | 481 |
| G | Elizabethport, New Jersey | 1910–1924 | 1870 |
| H | Elizabethport, New Jersey | 1906–1907 | 207 |
| J | Kilbowie (Clydebank), Scotland | 1904–1910 | 129 |
| JA | St. Johns, Quebec, Canada | 1924–1936 | prefix only |
| JB | St. Johns, Quebec, Canada | 1936–1948 | prefix only |
| JC | St. Johns, Quebec, Canada | 1948–1954 | prefix only |
| JD | St. Johns, Quebec, Canada | 1954–1961 | prefix only |
| JE | St. Johns, Quebec, Canada | 1961–onward | prefix only |
| K | Elizabethport, New Jersey | 1902–1904 | 250 |
| L | Elizabethport, New Jersey | 1901–1901 | 112 |
| M | Kilbowie (Clydebank), Scotland | 1900–1900 | 45 |
| N | Elizabethport, New Jersey | 1900–1900 | 120 |
| NA | Anderson, South Carolina | 1951–1959 | prefix only |
| NB | Anderson, South Carolina | 1959–1961 | prefix only |
| NC | Anderson, South Carolina | 1961–onward | prefix only |
| P | Kilbowie (Clydebank), Scotland | 1900–1901 | 115 |
| R | Kilbowie (Clydebank), Scotland | 1902–1903 | 142 |
| S | Kilbowie (Clydebank), Scotland | 1906–1907 | 121 |
| SA | Bonnières-sur-Seine, France | 1935–1958 | prefix only |
| SB | Bonnières-sur-Seine, France | 1935–1958 | prefix only |
| SC | Bonnières-sur-Seine, France | ?–1968 | prefix only |
| V | Kilbowie (Clydebank), Scotland | 1908–1909 | 109 |
| W | Bridgeport, Connecticut | 1940–1959 | 21 |
| Y | Kilbowie (Clydebank), Scotland | 1920–1935 | 768 |
Prefixes marked "prefix only" (JA–JE, NA–NC, SA–SC) have no published block-by-block ledger — Singer's dating table gives the years the series was issued, and the decoder answers with that range rather than inventing an exact year. W numbers come from the Bridgeport slide chart, which gives year ranges.
Plain numbers, allotted year by year from 1871 to 1899 in the surviving table. Below 611,000 the machine is from 1851–1870 and no published year split survives — the decoder says so instead of guessing.
One factory series at a time: N, L, K, B, D, then the long G run at Elizabethport; F, Y, J, M, P, R, S, V at Kilbowie in Scotland; C at Wittenberge; H at Elizabethport. Up to seven digits follow.
AA–AT at Elizabethport, EA–EX at Kilbowie, JA–JE at St. Johns in Canada, NA–NC at Anderson, South Carolina, SA–SC at Bonnières in France. Six digits follow.
Stamped into the cast bed: front-right on top on most pre-1950s machines, on a raised pad underneath on later ones. Treadle and hand-crank machines carry it on the bed as well. The number on the motor is the motor's serial and will not date the machine. Full walk-through on the serial location guide.
Use the longer, higher one. Machines often carry a second, shorter number — a part or casting number — that appears in no register.
It happens, mostly with low G numbers: Singer allotted some ranges twice, years apart. The decoder lists both entries with their machine classes; the class that matches your model is your entry.
Singer's model number for the block — 221 is the Featherweight, 201, 301 and 15 are other familiar classes. A letter after the class (221K, 99K) marks a Kilbowie-built machine.
Featherweights and clean early machines are where the money is — and where the mistakes are. The kit prices your exact model from sold listings and walks the condition checks that separate a $385 machine from a $900 one.
Included in the $39 Seller & Restore Kit