However if you have purchased a rail ticket it can be cancelled online. The rules are as follows

Cancellation of e- tickets.

• The e- ticket may be booked and cancelled through internet and the refund of fare shall be credited to the customers account after deducting the charges applicable.
• In case of a confirmed e-ticket, refund of fare shall be granted in accordance with rule for unused tickets on which reservation has been made. In case of RAC e-ticket, refund of fare shall be granted in accordance with rule for unused waitlisted and RAC tickets.
• In case of the waitlisted e-ticket on which status of all the passengers is on waiting list even after preparation of reservation charts, names of all such passengers booked on that Passenger Name Record (PNR) shall be dropped from the reservation chart and refund of fare shall be credited to the customer.s account after deducting the clerkage.
• In case on a party e-ticket or a family e-ticket issued for travel of more than one person, some persons have confirmed reservation and others are on the list of RAC and waiting list, then in case of passengers on RAC or waitlisted not travelling, a certificate has to be obtained from the ticket checking staff to that effect and refund of fare shall be processed online through TDR, indicating the details of the certificate issued by ticket checking staff.
• The online TDR shall be filed upto seventy two hours of actual arrival of the train at passenger.s destination and the original certificate issued by the ticket checking staff is to be sent through post to Indian Railway Catering and Tourism Corporation (IRCTC). The fare shall be refunded by Indian Railway Catering and Tourism Corporation (IRCTC) to the customer.s account after due verification.
• In case of e-tickets (confirmed or RAC), if the reservation charts have been prepared, online TDR is required to be filed for obtaining refund. No refund of fare shall be admissible on e- ticket having confirmed reservation in case the request for refund is filed online after two hours of the actual departure of the train.
• No refund of fare shall be admissible on RAC e-tickets in case the request for refund is filed online after three hours of the actual departure of the train.

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Cancellation is not possible on Internet. To cancel a ticket, the customer will have to submit the ticket at any computerized reservation (PRS) counter. The fare paid by the customer will be refunded electronically (as credit to the relevant credit/debit card account used for the transaction) after deducting cancellation charges. Bank charges that are being levied by the Payment Gateway/Banks are not subject to refund in the event of cancellation of tickets by the Customer. The cancellation charge is determined by the Indian Railway's rules for cancellation and is based on the time of cancellation and the status of the ticket. IRCTC service charge is not refunded. PRS counter will issue a cancellation ticket/receipt and IRCTC will credit the amount of refund due, to the customer's account. No cash refund will be given to the Customer. For further details please refer to the Indian Railways rules for Cancellation.