The Fiji National Provident Fund board has decided to extend membership of the fund, to casual, temporary and seasonal workers.
The Fiji Council of Trade Unions has welcomed the move, saying it will benefit cane cutters and farm labourers who are among the poorest workers.
It's general secretary, Attar Singh, says until now, the Provident Fund Act has allowed employers not to make contributions for those who worked less than 11 days a month.
Mr Singh says many employers have been taking advantage of this and deprived workers of their legitimate rights.
The Provident Fund is Fiji's biggest financial institution with assets in excess of 1-point-3 billion US dollars.