Any process that increases the rate, frequency or extent of fructose 1,6-bisphosphate 1-phosphatase activity. Fructose 1,6-bisphosphate 1-phosphatase activity is the catalysis of the reaction: D-fructose 1,6-bisphosphate + H2O = D-fructose 6-phosphate + phosphate.
positive regulation of fructose 1,6-bisphosphate 1-phosphatase activity