The University of Massachusetts offers two different voluntary retirement savings plans.

403(b) Plans
You may also defer some of your own income to a 403(b) plan, up to IRS limit of $19,000 if you are under 50 years old or $22,000 if you are 50 years old or over.  

457(b) Plan
If you meet eligibility requirements, you may also defer some of your own income to a 457(b) up to the IRS limit of $19,000 if you are under 50 years old or $22,000 if you are 50 years old or over.

Voluntary retirement plan information and enrollment is available by going to https://www.umassmed.edu/hr/benefits/retirement-plans/voluntary-retirement-plans/