Phuket, where the wage is currently 221 baht, highest in Thailand, is among seven provinces that were to trial the nationwide pay rise from January 1.
However, the floods that have killed more than 300 people and wrought economic havoc in parts of Thailand have led to the pioneering move being postponed for three months.
Today's decision of the Central Wage Committee in Bangkok is expected to be approved by Cabinet tomorrow.
Workers in Phuket and some other provinces around the country have already attempted to demand the 300 baht minimum rate, Phuketwan has learned, pointing to the pressure-cooker dangers of a boost to inflation.
Until now, every province in Thailand has had a minimum wage set based on its consumer price index, with the daily minimum varying from Phuket's high of 221 baht to 159 baht in the province with the lowest CPI.
Phuket in recent years has rapidly overtaken Bangkok as the most expensive place to live and the increase to 300 baht from April 1 can only lift living costs. The move was a promise made by the Pheu Thai Party in the July national election campaign, but since modified.
Phuket, Bangkok, Nakhon Pathom, Nonthaburi, Samut Prakan, Samut Sakhon, and Pathum Thani are to gain the 300 baht minimum from April 1 with other provinces likely to reach that figure by 2013.
The effect is likely to be greatest on Phuket, where a high proportion of workers are paid the daily rate.