Currently cartons of canned fish contain 12 cans, while cartons of corned beef contain four three-pound cans, at a cost of $US10 and $US34 respectively.
The new cartons will contain only eight cans of fish and two cans of beef.
Prime Minister Tuilaepa Sailele Malielegaoi said he expected that all wholesalers would have sold out of their old stock to make way for the new packaging requirements by the end of February.