Key Difference: A train in the Indian Railway system is made up of different coaches, which are roughly divided as air-conditioned and non-air-conditioned. The air-conditioned classes are First Class AC (1AC), AC Two Tier or Second Class AC (2AC), AC Three Tier or Third Class AC (3AC), and AC Chair Class. The 1AC is the most expensive and the one with the most amenities, the 2AC has less amenities, and is cheaper, while the 3AC has the least amenities, and is the cheapest.  

The Indian Railway system is a complicated network of stations and tracks. In fact, it is one of the world's largest railway networks. It is owned and operated by the Government of India through the Ministry of Railways. However, the system, especially because it is that big, can be really complicated to maneuver. In fact, even native Indians have trouble getting the information they need from the system. So, what chance do tourists have? Also see: The difference between e-ticket and i-ticket. 

Traveling in the Indian Railway is never as simple as just buying the ticket and boarding the train. Not only are there options like different trains, different routes, different times, as well as reservation, non-reservation, Tatkal, Premium Tatkal, but also options for the types of tickets that one wants.

A train is made up of different coaches, which are roughly divided as air-conditioned and non-air-conditioned. However the non-air-conditioned are further categorized into First class, Chair Class, Sleeper Class, Second Sitting, and Unreserved. The air-conditioned classes are First Class AC (1AC), AC Two Tier or Second Class AC (2AC), AC Three Tier or Third Class AC (3AC), and AC Chair Class.

The AC Chair Class and Chair Class are only available on trains that travel short distances, i.e. day trips. For trains that contain overnight trips, there are two ways to travel, the cheaper non-air conditioned classes, and the more expensive and luxurious air-conditioned classes. Let’s look at the three main types of air-conditioned coaches. 

Also see: Train Vs. Metro

As the name suggests, First Class AC (1AC), is the most expensive and luxurious accommodation that the Indian Railway offers. There are many amenities, such as but not limited to each compartment having only 2 or 4 berths. The compartments are often spacious and carpeted with a sink and individual reading lights. They are also lockable for privacy and are fairly non-crowded. Depending on the train in question, the compartments will also have charging points for mobiles and other electronics. The toilets are clean and showers are available. Food, pillows, sheets, and blankets are complimentary. However, these services don’t come cheap. Not only is the 1AC the most expensive berth on the train, but its prices can be comparative to a plane ticket at times.

See: Train Vs Tram

The Second Class AC (2AC) is usually a good compromise between amenities and cost. The 2AC compartments are still not crowded, as there usually only 4 berths in the compartment. There are only 2 berths in the aisle bay. However, the compartments do not have lockable doors, or doors at all, instead they have curtains for privacy. They do not have sinks either or the charging points but still have the individual reading lights. Pillows, sheets, blankets, and food are still complimentary. The toilets may not be as clean and with as many amenities, i.e. no shower, but they are still fairly decent. However, the prices of 2AC are quite affordable, especially when compared to 1AC, but they might still be out of budget for some.

This is where the AC Three Tier or Third Class AC (3AC) comes into play. It provides the basic amenities, still more than the non AC, but at a more affordable rate. There are no curtains or doors for privacy. It does not have sinks, charging points or individual reading lights. Food is not complimentary. However, it does provide clean areas, and pillows, sheets, and blankets are provided. The toilets are fairly clean, especially at the beginning of the journey, but may get dirty depending on the number of people. The compartments may seem crowded to some as there are 6 berths in the compartment, and 2 in the aisle bay. However, this crowd is still nothing when compared to the crowd in the non-air conditioned coaches, especially the unreserved class.

See: Difference between Metro and Local train

Comparison between 1AC, 2AC, and 3AC in Indian Railway:

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