I-ticket: An i-ticket refers to the normal Internet ticket, which IRCTC will courier to you at the address given by you while logging, which ticket you will receive at your doorstep in 2-3 days. For i-ticket you have to book a ticket at least three days prior to the date of journey to enable its delivery by courier. It can be booked under Confirmed/RAC/Waitlisted ticket status.
E-ticket: An e-ticket can be booked up to the time of the preparation chart for your train. This will require entering the identity particulars of one of the passengers, who will have to carry the same ID card while traveling. An
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can be booked only if the ticket status is Confirmed or RAC.
HOW TO CANCEL THE I-TICKETS AND GET REFUND?

Cancellation of I-Tickets can be done at any computerized reservation counter across the country and a cancellation ticket obtained. NO CASH REFUND will be given. Service Charge is not refundable. Refund of fare shall be made after deduction of cancellation charge. The refund amount will be credited to the respective account electronically through MoneyClickTM route. I-tickets can be cancelled even after the departure of the train, but subject to terms & conditions of IRCTC.

HOW TO CANCEL THE E-TICKETS AND GET REFUND?

E-tickets (Reservations) can be cancelled only through Internet till Chart preparation of the train and cancellation is not allowed at the Railway Counters. If you wish to cancel your E-ticket, you can do so till the time of chart preparation for the train (which is normally 4 to 6 hours before the scheduled departure of the train from the train originating station. (For trains starting up to 12 noon the chart preparation is usually done on the previous night). You can log on to www.irctc.co.in and go to Booked Tickets link and select the ticket to be fully or partly cancelled and can initiate the cancellation by selecting the passengers to be cancelled. However if the Identity Card holder in the original ticket is selected for cancellation, all the passengers in the ticket would be cancelled and a fresh reservation will have to be made, duly including the ID particulars of another passenger. Cancellation would be confirmed online and the refund would be credited back to the account used for booking as for normal Internet tickets. If there is any partial cancellation of ticket please ensure that the modified ticket (Electronic Reservation Slip) is printed separately. Modification on e-Tickets such as change of boarding point, change of Name is not permitted.