Massachusetts landlords must help the tenant maintain 64 to 68 °F from September 15 to June 15 under the Massachusetts heat laws. Massachusetts apartment heating laws are specified in the State Sanitary Code, officially 105 CMR 410 The Minimum Standards of Fitness for Human Habitation. This regulation has the force of law and governs all things apartment, including winter heating requirements.
Landlords have been fighting the free rent trick in Massachusetts for decades. There's a giant loophole in the Massachusetts General Laws, Chapter 239 Section 8A, that gives the tenant a "get out of jail free" card with evictions. We call this loophole "the free rent trick."