Highest salary at Polk County in year 2020 was $236,637. Number of employees at Polk County in year 2020 was 1,273. Average annual salary was $73,051 and median salary was $67,495. Polk County average salary is 56 percent higher than USA average and median salary is 55 percent higher than USA median salary. From 2019 to 2020, the average salary of employees at this employer increased 3.0 percent, the median salary increased 1.9 percent.