When it comes to navigating residential leases, two terms that often come up are sublet agreements and substitution agreements (also referred to as lease assignments). While both involve a transfer of occupancy, they serve different purposes and come with distinct implications. Let’s break down the differences between these two types of agreements, keeping in mind a few key considerations.
Boston is a highly mobile and university oriented city that has tens of thousands of sublet and substitution agreements happen every single apartment leasing season. Many students and young professionals often go on internships and study around the globe which opens up a lot of short term occupancy opportunities that need to be addressed in a professional manner. It is our goal to help you understand all the options and responsibilities that can occur with lease modifications and/or changes.

Sublet Agreements
A sublet agreement occurs when the original tenant (the sublessor) temporarily rents out all or part of the property to another party (the subtenant) while still retaining responsibility for the original lease. In this arrangement, the original lease remains intact between the landlord and the original tenant, and the landlord’s written permission to sublet is typically required. Most landlords in the Greater Boston Area understand and accept subletting. However, it is super important that you read any addendum before singing any lease because there are a few landlords that simply refuse to allow subletting.
Key Features of a Sublet Agreement:
- Responsibility: The original tenant remains legally responsible for the lease terms, including paying rent to the landlord. If the subtenant fails to pay rent or damages the property, the original tenant remains liable.
- Payment Structure: The subtenant usually pays…