Highest salary at Town of Grantham in year 2020 was $85,584. Number of employees at Town of Grantham in year 2020 was 19. Average annual salary was $52,259 and median salary was $47,748. Town of Grantham average salary is 12 percent higher than USA average and median salary is 10 percent higher than USA median salary. From 2019 to 2020, the median salary increased 2.9 percent.