Marshall has printed date information on its amps since July 1969, and that numbering is one of the few maker systems that can give a year from the plate alone. Everything from 1962 to June 1969 has no serial system at all and is dated from cosmetics, chassis details and transformers. Marshall publishes no dating page, so these tables come from the collector literature and from the company's own barcode and date-bar formats.
The first Marshall amps (JTM-45 heads and combos, 1962–64) have no standard serial number: numbers were stamped inside the back panel and were not systematic. Transformer marks carry the dating — Drake 784-084 on 100W amps and 784-139 on 50W — although sources disagree about when Drake gave way to Dagnall.
Perspex panels, block logos and specific tolex and grille-cloth combinations bracket these years, and the collector checklists for them are detailed. No serial number format has been identified for this window.
From July 1969 the plate carries a model code, a number and a year letter at the end, and the letter scale is what makes a year readable. In 1984 the letter moved into the middle of the number and the same scale continued to September 1992.
The 800 series (2203 and 1959 heads plus combos, 1981–1990) and the 900 series (1990–1992 in the catalogue) fall inside the two letter-position eras. Silver Jubilee amps (1987–89) sit alongside them.
A barcode sticker replaced the letter system in October 1992 and carries year and week. From August 1997 a date bar adds a country letter, a voltage letter and a four-digit sequence, and cabinets carry Celestion speaker codes of their own.
| Series | Years | Rows | Era note |
|---|---|---|---|
| Pre-standard four-digit numbers | 1962–1964 | 1 | 1962–1964 |
| Model code + number + year letter (letter at the end) | 1969–1983 | 14 | July 1969 – 1983 |
| Model code + year letter + number (letter in the middle) | 1984–1992 | 8 | 1984 – September 1992 |
| Barcode sticker xx-xxxxx-xx | 1992–1997 | 6 | October 1992 – July 1997 |
| Country–year–week–number–voltage bar | 1997 | 1 | August 1997 to today |
20 Marshall models are catalogued with their production years, specs and safety notes.
Browse the models →On plates from July 1969 to 1983 the final character is the year letter; from 1984 to September 1992 the letter sits in the middle of the number. The scale runs upward from A, but it stops being public after Z.
No. 1959 is the model code for a 100W head, and the same is true of 1987, 1962 and 2203.
Barcode stickers ran from October 1992 to July 1997 and the date bar from August 1997, so an amp built across the changeover can carry both.
No. Marshall has no published serial system for 1965 to June 1969; cosmetics and component codes are the only witnesses.
Compiled from 150 published sources — the source library.