- Liberty Mutual Group
- Lions Eye Bank for Long Island
- Little Sisters of the Poor - Brooklyn
- LiveOnNY
- Loews Hotels
- Long Beach Memorial Medical Center
- Long Island Head Start
- Long Island Jewish Forest Hills
- Long Island Jewish Medical Center
- Long Island Jewish Valley Stream
- Long Island Marriott
- Long Island State Veterans Home at Stonybrook University
- M.R. Beal and Co.
- Mad Dogs Enterprises
- Maimonides Medical Center
- Maimonides Midwood Community Hospital
- Manhattan Borough President's Office
- Manhattan Chamber of Commerce
- Manhatten Bagels
- Margaretville Memorial Hospital
- Marken
- Marsh USA, Inc.
- Marymount Manhattan College
- Masonic Care Community of New York
- Massena Memorial Hospital
- Mather Hospital
- McFarland-Johnson, Inc.
- MecyFirst
- Medical Society of the State of New York
- Medina Memorial Hospital
- Mediprime Group Ltd.
- Meetup
- Mercy Hospital of Buffalo
- Mercy Medical Center
- Midhudson Regional Hospital of Westchester Medical Center
- Millard Fillmore Suburban Hospital
- Mohawk Valley Health System - St. Elizabeth Campus
- Monroe College Bronx Campus
- Montefiore Medical Center - Einstein Campus
- Montefiore Medical Center - Moses Campus
- Montefiore Medical Center - New Rochelle Campus
- Montefiore Medical Center - Wakefield Campus
- Montefiore Mount Vernon Hospital
- Montefiore Nyack Hospital
- Montefiore St. Luke's Cornwall
- Montefiore Westchester Square Campus
- Moog, Inc
- Morgan Stanley Dean Witter
- Morningside House Nursing Home
- Mount Sinai Beth Israel