Highest salary at Grundy County in year 2020 was $176,323. Number of employees at Grundy County in year 2020 was 197. Average annual salary was $50,611 and median salary was $41,861. Grundy County average salary is 8 percent higher than USA average and median salary is 4 percent lower than USA median salary. From 2019 to 2020, the average salary of employees at this employer increased 2.3 percent, the median salary increased 6.9 percent.