| Ruiz, Dan | High School Building Committee | | | |
| Russian, DonnaRose | Election Modernization Committee, Republican Town Committee | | | |
| Russo, Anmarie | Veterans Council (6/30/2018) | | | |
| Ryan-Vollmar , Susan | Co-Chair, Civilian Police Advisory Board Study Committee, LGBTQIA+ Rainbow Commission | Town Manager | | susanryanvollmar@gmail.com |
| Samenfeld, Scott | Arlington Cultural Council, Publicity, 4/30/2022 | | | |
| Sankalia, Priya | | Boards & Commissions, Finance Committee, Select Board, Town Manager | | |
| Sankalia, Priya | Zero Waste Arlington | | | |
| Savarese, Steve | Realtor, At Large, 2025 | Boards & Commissions, Town Manager | | |
| Sawtelle, Steven | Veterans Council (1/31/2018) | | | |
| Schaefer, Dianne | Historical Commission | Boards & Commissions | | |
| Schiller, Jacob | Semiquincentennial Committee, Menotomy Minute Men | | | |
| Schlichtman, Paul | Building Committee (PTBC), School Committee Liason | | | |
| Schlichtman, Paul | Chair, School Committee, 2026 | Boards & Commissions, Town Manager | (617) 755-4300 | pschlichtman@arlington.k12.ma.us |
| Selker, Paul | Master Plan Update Advisory Committee | Town Manager | | |
| Shah, Kristine | Local Emergency Planning Committee, Council on Aging | Boards & Commissions, Town Manager | | |
| Shah, Kristine | Sustainable Transportation, HHS | | | |
| Shea, Elizabeth | Bicycle Advisory Committee Rep. | | | |
| Sheppard, Patricia | Local Emergency Planning Committee, Chief Technology Officer | Boards & Commissions, Town Manager | | |
| Shoemaker, Linda | Minuteman Bikeway 25th Anniversary Committee | | | |
| Simon, Hannah | Board of Youth Services, 2019 | Boards & Commissions | | |
