Highest Kelso employee salary in year 2017 was $178,330. Kelso employees number in year 2017 was 691. Kelso average salary was $46,083 and median salary was $43,300. According to the last payroll, Kelso average salary is 38 percent lower than USA average and 37 percent lower than Washington state average. Kelso employee salaries are usually between $19,123 and $67,881. Top 10% of highest-earning employees have salaries ranging from $81,670 to $178,330.