Mainline Plumbing

Mainline Plumbing serves the Londonderry, New Hampshire community with a 5.0-star rating across 629 reviews. Technicians arrive in marked vehicles equipped with the parts needed to complete most repairs during the initial visit, and the crew leaves the worksite clean before departing. Customers in the area consistently mention the team's ability to diagnose problems quickly and explain findings in terms a homeowner can understand.

The company handles water heater replacements, piping updates, and whole-house filtration system installations. Multiple reviewers describe receiving same-day service when their systems failed, with one technician completing a full water heater and piping installation within a few hours. The team also assists homeowners with applying for state rebates on qualifying equipment, a process one customer noted saved them thousands of dollars on a filtration system purchase.

Reviewers name specific technicians including Conner, George, John, Mike, and Mike E., describing scenarios ranging from emergency same-day water heater swaps to fixing a broken garbage disposal. One customer noted John walked through replacement options on an outdated polybutylene system and returned the next day for the installation. Another mentioned Mike arrived immediately after the initial call and provided a Senior Citizen discount on the service call.