Indian Post Office Act, 1898
43. Power to maintain money order system and to make rules as to remittances thereby
(1) The Central Government may provide for the remitting of small sums of money through the Post Office by means of money orders, and may make rules as to such money orders.
(2) In particular and without prejudice to the generality of the foregoing power, such rules may prescribe-
(a) the limit of amount for which money orders may be issued;
(b) the period during which money orders shall remain current ; and
(c) the rates of commission or the fees to be charged on money orders or in respect thereof.