In Canada, the "Pioneer Era" of postcards extended from 1871 to about 1898. In that period, the Post Office was the only establishment that was allowed to print post cards. The Post Office started issuing pre-stamped, pictureless post cards on June 1, 1871. They were called postal stationery cards and sold for one cent at the post office (a regular letter needed two cents to mail). The one cent price included both the cost of the card and the delivery to any address within the Dominion. "The front or stamped side of the card is to be used for the address only. There must be nothing else either written or printed upon it. On the other or reverse side, any communication whether of the nature of a letter or otherwise, may be written or printed." Postal Stationery Cards were used for business purposes to make appointments, confirm orders and arrange deliveries.
This is a typical Postal Card: it is to John Lemp from Valentine Stock reminding him that his next installment to the Tavistock Mill Fund is due. .