These are issued by the Reserve Bank of India on behalf of the Government of India and are thus actually a class of Government Securities. At present, T-Bills are issued in maturity of 14 days, 91 days and 364 days. The RBI has announced its intention to start issuing 182 day T-Bills shortly. The minimum denomination can be as low as Rs.100, but in practice most of the bids are large bids from institutional investors who are allotted T-Bills in dematerialized form. RBI holds auctions for 14 and 364 day T-Bills on a fortnightly basis and for 91 day T-Bills on a weekly basis. There is a notified value of bills available for the auction of 91 day T-Bills which is announced 2 days prior to the auction. There is no specified amount for the auction of 14 and 364 day T-Bills. The result is that at any given point of time, it is possible to buy T-Bills to tailor one's investment requirements.

Potential investors have to put in competitive bids at the specified times. These bids are on a price/interest rate basis. The auction is conducted on a French auction basis ie all bidders above the cut off at the interest rate/price which they bid while the bidders at the clearing/cut off price/rate get pro rata allotment at the cut off price/rate. The cut off is determined by the RBI depending on the amount being auctioned, the bidding pattern etc. By and large, the cut off is market determined although sometimes the RBI utilizes its discretion and decides on a cut off level which results in a partially successful auction with the balance amount devolving on it. This is done by the RBI to check undue volatility in the interest rates.

Non-competitive bids are also allowed in auctions (only from specified entities like State Governments and their undertakings and statutory bodies) wherein the bidder is allotted T-Bills at the cut off price.