In the early 1800's a crew of Italian and Spanish men came down the Peace River dredging for phosphate. When they arrived at the springs, which smelled strongly of sulphur, the Italians named them Zolfo for the sulphur water there. That is how Zolfo got its name.
The first settler in the area was David D. Mahan. He took up residence in Zolfo in 1878.
In 1886 Florida Southern Railroad opened a depot in Zolfo. A post office was established on May 26, 1886.
The first council meeting was held October 18, 1901. The Town was incorporated in 1904 and held its first official Town Council Meeting on October 18, 1904.
On September 13, 1909 the name was changed to Zolfo Springs.
In 1913 the citizens of Zolfo Springs decided that the town was in need of a water works. They believed that a supply of water could be obtained from an artesian well. A four-inch well was drilled approximately 465 feet deep, at which depth they struck a flow of water that spouted twelve feet above ground level. The Cameron and Barkley Company from Tampa was authorized to build the towns water works at a bid price of $1600.00. The town's population at this time was around 250 people-- making Zolfo Springs one of the smallest towns in the United States to own its own water works.
The first sidewalks were installed in the fall of 1917 by W.C. Robertson Company in Bartow.