The DMS/DM classes were numbered in a common sequence from 1 to 2646. The registration number matched the last 3 digits of the fleet number (except DM 1000 & DMS 2000), a practice that went back to Trolleybus days.
| DMS 1 - DMS 136 | EGP 1J - EGP 136J |
| DMS 137 - DMS 414 | JGF 137K - JGF 414K |
| DMS 415 - DMS 695 | MLK 416L - MLK 695L |
| DMS 696 - DMS 900 | TGX 696M - TGX 900M |
| DMS 901 - DMS 917 | SMU 901N - SMU 917N |
| DM 918 - DM 947 | SMU 918N - SMU 947N |
| DM 948 - DM 999 | GHV 948N - GHV 999N |
| DM 1000 | GHV 500N |
| DM 1001 - DM 1124 | GHV 1N - GHV 124N |
| DM 1125 - DM 1247 | KUC 125P - KUC 247P |
| DMS 1248 - DMS 1297 | JGU 248K - JGU 297K |
| DMS 1298 - DMS 1499 | MLH 298L - MLH 499L |
| DMS 1500 - DMS 1702 | THM 500M - THM 702M |
| DM 1703 - DM 1720 | THM 703M - THM 720M |
| DM 1721 - DM 1739 | SMU 721N - SMU 739N |
| DM 1740 - DM 1832 | GHM 740N - GHM 832N |
| DMS 1833 - DMS 1897 | GHM 833N - GHM 897N |
| DMS 1898 - DMS 1999 | KUC 898P - KUC 999P |
| DMS 2000 | KJD 500P |
| DMS 2001 - DMS 2024 | KJD 1P - KJD 24P |
| DMS 2025 - DMS 2057 | OUC 25R - OUC 57R |
| DMS 2058 - DMS 2122 | KJD 58P - KJD 122P |
| DMS 2123 - DMS 2267 | OJD 123R - OJD 267R |
| DMS 2268 - DMS 2346 | THX 268S - THX 346S |
| DMS 2347 - DMS 2472 | OJD 347R - OJD 472R |
| DMS 2473 - DMS 2526 | THX 473S - THX 526S |
| DM 2527 - DM 2646 | THX 527S - THX 646S |
London Transport gave chassis codes and body codes to its buses. For example DMS 1-17 had chassis code 1DM and body code DM1. The complete vehicles were known as 1DM1.
A very basic break down would be :-
| CHASSIS CODE | ENGINE |
| 1DM | Gardner 6LXB |
| 2DM | Leyland O.680 |
| 3DM | Leyland O.690 turbocharged |
| BODY CODE | BODY | BATCH |
| DM1 | PRV standard | 1971 |
| DM2 | not used | not used |
| DM3 | PRV standard | 1972-1974 |
| DM4 | MCW standard | 1972-1974 |
| DM5 | PRV standard | 1975-1976 |
| DM6 | PRV B20 | 1975-1976 |
| DM7 | MCW standard | 1975-1976 |
| DM8 | MCW B20 | 1975-1976 |
Standard is an un-official term used to describe the non B20s.
Other points
are :- All DMs had Leyland engines (except DM 1199) and had body codes DM3/3,
DM4/3 & DM6/1.
| 1DM | 1-117 | Gardner | |
| 2/1DM | 118-131, 133-367 | Gardner | |
| 3/1DM | 368-494, 1248-1371 | Gardner | |
| 4/1DM | 608-611, 617-619, 637-639, 655, 659-660, 1452-1467, 2038-2057, 2128-2246 | Gardner | |
| 2DM | 495-587, 1372-1427 | Leyland | |
| 1/2DM | 132 | Leyland | |
| 2/2DM | 588-607, 612-616, 620-636, 640-654, 656-658, 661-853, 855-1140, 1145, 1185, 1428-1451, 1468-1906 | Leyland | |
| 3/2DM | 1141-1144, 1146-1184, 1186-1247, 1907-2037, 2058-2127 | Leyland | |
| 3DM | 854, 2247-2646 | Leyland B20 |
DMS 864, DM 1199, DMS 1968, DMS2059 and DMS 2120 had Rolls Royce engines but this did not affect the chassis codes.
| DM1 | 1-17, 118-167 | PRV | DMS | Headlights original position |
| DM1/1 | 18-117 | PRV | DMS | recoded DM1 |
| DM1/2 | 168-367 | PRV | DMS | Headlights re-positioned |
| DM3 | 368-585, 595-596 | PRV | DMS | '1972' bodies |
| DM3/1 | 586-594, 597-853, 855-917 | PRV | DMS | '1973/4' bodies |
| DM3/3 | 918-1217 | PRV | DM | '1973/4' bodies |
| DM3/5 | 854 | PRV | DMS | Prototype B20 |
| DM4 | 1248-1427 | MCW | DMS | '1972' bodies |
| DM4/1 | 1428-1702, 1833-1967 | MCW | DMS | '1973/4' bodies |
| DM4/3 | 1218-1247, 1703- 1832 | MCW | DM | '1973/4' bodies |
| DM5 | 2058-2166 | PRV | DMS | '1975/6' bodies |
| DM6 | 2347-2526 | PRV | DMS | B20 |
| DM6/1 | 2527-2646 | PRV | DM | B20 |
| DM7 | 1968-2057, 2167-2246 | MCW | DMS | '1975/6' bodies |
| DM8 | 2247-2346 | MCW | DMS | B20 |
Further sub-codes were used to denote buses with fareboxes or ticket cancelling equipment.
| Gardner 6LXB | DMS 1-131 |
| Leyland O.680 | DMS 132 |
| Gardner 6LXB | DMS 133-494 |
| Leyland O.680 | DMS 495-607 |
| Gardner 6LXB | DMS 608-611 |
| Leyland O.680 | DMS 612-616 |
| Gardner 6LXB | DMS 617-619 |
| Leyland O.680 | DMS 620-636 |
| Gardner 6LXB | DMS 637-639 |
| Leyland O.680 | DMS 640-654 |
| Gardner 6LXB | DMS 655 |
| Leyland O.680 | DMS 656-658 |
| Gardner 6LXB | DMS 659-660 |
| Leyland O.680 | DMS 661-853 |
| Leyland O.690 | DMS 854 |
| Leyland O.680 | DMS 855-863 |
| Rolls Royce Eagle | DMS 864 |
| Leyland O.680 | DMS 865-917 |
| Leyland O.680 | DM 918-1198 |
| Rolls Royce Eagle | DM 1199 |
| Leyland O.680 | DM 1200-1247 |
| Gardner 6LXB | DMS 1248-1371 |
| Leyland O.680 | DMS 1372-1451 |
| Gardner 6LXB | DMS 1452-1467 |
| Leyland O.680 | DMS 1468-1702 |
| Leyland O.680 | DM 1703-1832 |
| Leyland O.680 | DMS 1833-1967 |
| Rolls Royce Eagle | DMS 1968 |
| Leyland O.680 | DMS 1969-2037 |
| Gardner 6LXB | DMS 2038-2057 |
| Leyland O.680 | DMS 2058 |
| Rolls Royce Eagle | DMS 2059 |
| Leyland O.680 | DMS 2060-2119 |
| Rolls Royce Eagle | DMS 2120 |
| Leyland O.680 | DMS 2121-2127 |
| Gardner 6LXB | DMS 2128-2246 |
| Leyland O.690 | DMS 2247-2526 |
| Leyland O.690 | DM 2527-2646 |
| Park Royal | DMS 1-917 |
| Park Royal | DM 918-1217 |
| MCW | DM 1218-1247 |
| MCW | DMS 1248-1702 |
| MCW | DM 1703-1832 |
| MCW | DMS 1833-2057 |
| Park Royal | DMS 2058-2166 |
| MCW | DMS 2167-2346 |
| Park Royal | DMS 2347-2526 |
| Park Royal | DM 2527-2646 |
London Transport gave it's buses body numbers, the sequence had reached 9227 when the last RT had been delivered. The Routemasters were numbered in a new series from 1 upwards, prefixed by a 'B'. The A series was used for the XA, XF, and RC classes. The 'C' series was used for the Merlins and the 'E' series for the Swifts. Perhaps by coincidence or perhaps not the DMS / DM classes had body numbers D1 to D2646. As no body swapping occurred with the Fleetlines the body and fleet numbers always matched up. Both numbers were carried on the circuit breaker covers in the cab. The practice of allocating body numbers came to an end with the delivery of the last DM.