Group Classifications & Percentage Charts

Massachusetts law assigns each member to a Group Classification based on their occupation, position, or job duties. Throughout your career, you may hold roles that fall into more than one group.

How Group Classification Affects Your Retirement Benefit

Your Group Classification and membership date determine the age factor used when calculating your retirement allowance. These age factors — combined with your creditable service and average salary — help determine your benefit percentage at retirement.

Below are links to the applicable percentage charts and age factor tables.

Middlesex County Retirement System Group Classifications

Group 1

K
L

Officials and general employees, including clerical, administrative, and technical staff, laborers, mechanics, dispatchers and all other positions not specifically assigned to another group.

Group 2

K
L
Select statutory occupations, including certain public safety–adjacent roles such as ambulance attendants and licensed electricians employed as such by a municipality.

Group 4

K
L
Public safety personnel, including police officers, firefighters, and certain employees of municipal electric light departments.

Need More Information?

Learn how your group classification, age factor, and creditable service determine your retirement allowance.