The contractors on this list participate in the Mass Save Home Energy Services Program and serve Massachusetts residential customers of the Sponsors (Berkshire Gas, Blackstone Gas, Cape Light Compact, Columbia Gas of Massachusetts, Eversource, Liberty Utilities, National Grid, and Unitil). Participating Home Performance Contractors (HPCs) are eligible to perform Home Energy Assessments and implement approved weatherization improvements (insulation and/or air sealing). In order to participate in the Mass Save Home Energy Services Program and work with the contractors listed, you must: (1) have an active residential natural gas account from one of the Sponsors OR an active residential electric account from one of the Sponsors if the customer resides in a non-gas-heated home and (2) occupy a 1-4 family home. Mass Save offers standardized pricing for program-approved weatherization improvements for your convenience; soliciting several quotes is not required. Weatherization work associated with new construction, additions, renovations, or any other projects where weatherization work is required to be completed in order to meet state or local codes, are not eligible for the Home Energy Services Program incentives. Other restrictions may apply. Please note, the Sponsors of Mass Save do not endorse, guarantee, or warranty any particular contractor, manufacturer, or product. All Participating Contractors have provided proof of licenses and insurance in the state of Massachusetts and have completed program required training.