Save $75 per window when you upgrade your single-pane windows to ENERGY STAR® "Most Efficient" certified windows.
A child looking out energy efficient windows
ENERGY STAR® Most Efficient certified windows can help reduce energy costs, put a stop to cold drafts in the winter, and reduce UV sun damage to floors, carpets, and furniture.

A typical home can expect savings of $101 to $583 a year when replacing single-pane windows with ENERGY STAR® Most Efficient certified models. Lower energy consumption also reduces greenhouse gas emissions from homes.

  1. Verify Existing Windows

    To qualify for this incentive, your existing windows must be verified during a Home Energy Assessment or a Virtual Special Home Visit. During this assessment, an Energy Specialist will assess your current energy usage and recommend improvements to save energy in your home (like insulation and air sealing upgrades, window upgrades, etc.).

    The specialist will also verify the number of windows you are eligible to replace. If they determine that air sealing and insulation upgrades are needed, you will be required to make these changes in order to receive incentives for the window replacements.

    These upgrades will maximize the efficiency of installing new windows

  2. View Qualifying Windows
    The windows must be certified by ENERGY STAR® for the Northern Region and listed on their "Most Efficient" list.

    Visit and select Most Efficient and northern region to find qualified windows.

  3. Purchase and Install Windows
    Purchase and install the number of ENERGY STAR® certified windows verified for eligibility during your assessment.
  4. Submit Rebate Form with Required Documentation
    Apply Online
    Print & Mail Rebate Form
  • This offer is only open to Massachusetts residential electric and gas customers where the Mass Save Program is offered by Berkshire Gas, Cape Light Compact, Eversource, Liberty, National Grid, or Unitil
  • Only for ENERGY STAR® Most Efficient certified for the north region windows replacing single-pane.
  • Existing windows must be verified prior to installing windows and applying for rebate. Get started at
  • Customer must complete weatherization recommendations made during the assessment to qualify
  • The rebate is good for purchases made from January 1, 2024, through December 31, 2024
  • Applications for 2024 rebates and all necessary materials must be postmarked or submitted online by January 31, 2025.

The Sponsors of Mass Save offer 0% financing HEAT Loans to make energy efficiency upgrades more affordable to Massachusetts residents. Through this loan, you could qualify for a loan up to $50,000 toward qualified home improvements.

An energy efficient home in Massachusetts

Case Study: 175-Year-Old Home Energy Improvements

A homeowner in Fairhaven took advantage of incentives on upgrades, including insulation, advanced power strips, LED lighting, a new boiler, and a mini-split heat pump—saving $723 annually in energy costs.

An energy efficient home in Massachusetts

Case Study: As Good as New

Instead of moving, Vance participated in a no-cost energy assessment to find ways to make his home more comfortable. By making insulation upgrades and installing two high-efficiency mini-split heat pumps and advanced power strips, he saved $632 annually in energy costs.