Q. What does a 4-digit train number (1989-2010) signify?
From 1989 onwards, and until replaced in Dec. 2010, for long-distance passenger trains, a 4-digit scheme was used. These 4-digit numbers were referred to as 'universal numbers', since they were unambiguous across the different zones, in contrast to the old train numbers that were not necessarily unique across different zones.
(The second and third digits of the new (2011 and later) 5-digit numbers signify the zone and division with the same system.)
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The first digit indicates the region or zonal railway, as indicated below:
0 is for Konkan Railway
1 is for CR, WCR and NCR(?)
2 is for superfasts, Shatabdi and Jan Shatabdi trains regardless of zones
3 is shared by ER and ECR
4 is for NR, NCR and NWR
5 is shared by NER and NFR
6 is for SR and SWR
7 is shared by SCR and SWR
8 is for SER and ECoR
9 is for WR, NWR and WCR
If the first digit is not '2', then the second digit indicates the division of the home shed or station that "owns" the rakes used for the train (the primary maintenance depot). This is usually in the same division as that of one of the end-points of the train's run, but sometimes it isn't. Usually, '0' for the second digit indicates the headquarters of the zone.
[3/00] A listing of the 2-digit prefixes and the corresponding home stations is given below. The "other" notation indicates the prefix is used for other home sheds in the zone that don't have their own prefixes. Prefixes not listed are not known to be in use.
Central and West-Central Railways
CR seems to have numbers that are a little less systematic than the other zones
10 is for Mumbai CST, also some Pune trains
11 is for Jhansi (??)
12 is for Bhopal (WCR)(
13 is for some fast passengers from Mumbai CST
14 is for Solapur and Jabalpur(WCR) divisions. (Also is, or was, for Nagpur and Bhusawal division trains (Manmad/Bhusawal)?)
15 : ?? one Dadar-bound train (Mumbai CST division), one Katni-bound train (Jabalpur division ??)
16 : ?? some Bhopal-bound trains
It is hard to make sense of CR's numbering. [8/03] The Mumbai CST - Solapur Siddheshwar Exp. has numbers 1423/1424, most likely because it shares the rake with some other train based at Nagpur. 1401/1402 and 1403/1404 run between Manmad and LTT / CSTM, while 1439/1440 runs Dadar-Nagpur, 1463/1464 runs Jabalpur - Rajkot, 1447/1448 is Jabalpur - Howrah, 1423/1424 is CSTM - Solapur, 1451/1452 is Nagpur - Gaya.
Eastern and East Central Railway
30 is for Howrah
31 is for Sealdah
32 is for Danapur
33 is for Dhanbad
34 is for Malda
35 is for Asansol
Northern, North Central and North Western Railway
40 is for New Delhi
41 is for Allahabad (NCR)
42 is for Lucknow
43 is for Moradabad
44 : other
45 is for Ambala
46 is for Firozpur
47 is for Bikaner(NWR)
48 is for Jodhpur(NWR)
North-Eastern and North-east Frontier Railways
50 is for Lucknow (BG, NER)
51 is for Varanasi (BG, NER)
52 is for Sonepur / Samastipur (BG, NER)
53 is for Izzatnagar / Lucknow (MG, NER)
54 is for Varanasi (MG, NER)
55 is for Samastipur (MG, NER)
56 is for Lumding (BG, NFR)
57 is for Katihar (BG/MG) / Alipurduar (BG) (NFR)
58 is for Lumding / Alipurduar (MG, NFR)
59 is for Tinsukia (NFR)
Southern and South-Western Railways
60 is for Chennai
61 is for Chennai Egmore
62 is for Mysore (SWR)
63 is for Thiruvananthapuram
64 is not in use
65 is for Bangalore (SWR)
66 is for Palghat
67 is for Madurai
68 is for Trichy
South-Central and South-Western Railways
70 is for Secunderabad
71 : other
72 is for Vijayawada
73 is for Hubli (SWR, BG)
74 is for Guntakal (BG)
75 is for Hyderabad
76 is for Kacheguda
77 is for Guntakal (MG) (no longer used because of gauge conversion)
78 is for Hubli (SWR, MG) (no longer used because of gauge conversion [9/03])
South-Eastern, South-East Central and East-Coast Railways
80 is for Kharagpur
81 is for Chakradharpur
82 is for Bilaspur
83 is for Sambalpur and others
84 is for Khurda Road
85 is for Waltair
86 is for Adra
Western, North-Western and West-Central Railways
90 is for Mumbai
91 is for Vadodara
92 is for Bhavnagar (BG)
93 is for Ratlam
94 is for Kota (WCR)
95 : other
96 is for Ajmer (NWR)
97 is for Jaipur (NWR)
98 is for Bhavnagar (MG)
99 is for Rajkot
If the first digit is '2', it indicates a train designated as "superfast", Rajdhani Express, Shatabdi Express, or Jan Shatabdi Express; in this case, the second digit indicates the zonal railway, as shown below:
20 is for Shatabdis and Jan Shatabdis on all zonal railways
21 is for superfasts on CR and WCR (formerly only CR)
22 is for superfasts from various zones - NR, NCR, NWR (formerly only NR). (Also some SR?) [5/05]
23 is for superfast on ER and ECR
24 is for superfast on NR, NCR and NWR (formerly only NR)
25 is for superfast on NER and NFR
26 is for superfast on SR and SWR (formerly only SR)
27 is for superfast on SCR and SWR (formerly only SCR)
28 is for superfast on SER, SECR and ECoR (formerly only SER)
29 is for superfast on WR, WCR and NWR (formerly only WR)
Until recently, no trains had 22xx numbers. Starting in July 2005, some superfast trains have been allotted numbers in this series, e.g., 2229/2230 Lucknow - New Delhi Mail. This has probably been done because some of the other superfast number ranges, especially 24xx and 26xx, are getting filled up.
As mentioned above, the division that owns the rakes may not be one of the end-points of the train. E.g., the Tirupati-Mumbai Exp. has numbers 6353/6354 because the rakes come from Trivandrum, and are shared with the Nagercoil-Tirupati Exp. (6351/6352). The Shaheed Exp. between Delhi and Darbhanga is numberd 4649, but 46 is the Firozpur division and neither terminus for the train is in that division.
A train between Jammu Tawi and Amritsar, both in the Ferozpur division of NR (45) has numbers 9113/9114, indicating the Vadodara division of WR! In all these cases the rakes are shared with other trains that do go through the referenced division. There are some other such anomalies.
In some rare cases, the division prefixes of the two trains of an up/down pair are different. E.g. Tirupati-Trichy Exp. which was 6799/6800 (67 - Madurai, 68 - Trichy). In this particular case the reason is that the old numbers for the train were 199/200, and IR has generally tried to retain the last two digits in converting the old numbers to 4-digit numbers. But there are some other rare cases where the up and down trains have different division prefixes, and this could indicate the two divisions sharing in rake maintenance, or could just be anomalies in the numbering system.
Sometimes two trains with the same name and same endpoints may have different numbers because they take different routes on different days of the week. E.g. 2303 Poorva Exp. : Howrah - Asansol - Patna - Mughal Serai - Allahabad - New Delhi (Mon - Tue - Fri - Sat); and 2381 Poorva Exp. : Howrah - Asansol - Gaya - Mughal Serai - Varanasi - Allahabad - New Delhi (Wed - Thu - Sun). [8/01].
Some non-mail, non-express, non-superfast trains also use this numbering scheme (e.g., some of the trains with the designation "fast passenger"). Commuter locals, some passenger services, etc. do not follow this scheme. These local trains and passenger services tend to use two or three-digit numbers, which may not be unique across zones. Central Railway tends to use 4-digit numbers for all its local passenger services.
Some trains that split or merge at various points, or which have sectional carriages ("slip coaches" as they are sometimes termed) might have additional suffixes ('A', 'B', etc.) in addition to the 4-digit numbers to distinguish among the different portions of the train. E.g., the 6635 down Netravati Exp. bifurcated at Shoranur (earlier at Palghat); 6635A was one half of it that went to Mangalore, while 6635B was the other half that went to Cochin.
Source : IRFCA.