Highest City of Monmouth employee salary in year 2023 was $73,878. City of Monmouth employees number in year 2023 was 25. City of Monmouth average salary was $30,082 and median salary was $18,782. According to the last payroll, City of Monmouth average salary is 60 percent lower than USA average and 52 percent lower than Illinois state average. City of Monmouth employee salaries are usually between $11,429 and $45,457. Top 10% of highest-earning employees have salaries ranging from $69,986 to $73,878.