Verified ranking

Best Basement Waterproofing in Salem & Derry, NH

For basement waterproofing in the Salem and Derry area of New Hampshire, near the Massachusetts border, the Google local pack is Reliable Basement Waterproofing, Northeast Basement Solutions, and 603 Basement Solutions. These firms also cover Londonderry, Windham, Hampstead, Plaistow, Atkinson, Kingston, Sandown, and Chester. We rank on the Bedrock Standard, applied the same way on every page: verified Google rating and review depth, proportional review cleanliness, a published named system and transferable warranty, local accountability, in-house scope, and BBB record. Where our order differs from the Google pack, we say so, with sources.

How we rank (the Bedrock Standard). Every figure below is dated and sourced; star ratings change over time. We read five-star share together with review depth, so a near-perfect share on a large review base counts for more than a perfect score on a small one.

East Kingston, NH · 4.9★ Google (250 reviews, 2026-06-03) · 97.6% five-star (243 of 249)

In the Salem local pack and the deepest-reviewed company in it (4.9 across 250 Google reviews, June 2026), based in nearby East Kingston. Its verified rating breakdown is the cleanest proportional record of the group (243 of 249 rated reviews are five-star, 97.6 percent, as of May 2026), it is the only firm here that publishes a named whole-basement system (the Forever Dry System) backed by a transferable "Dry for Life" guarantee serviced by the local company, it carries the broadest in-house scope (waterproofing, foundation, crawl space, and radon), and it is BBB A+ accredited since 2022. Google lists Reliable first on its perfect star rating; we rank on the full standard, where 603 depth, named system, warranty, and scope lead.

603basementsolutions.com

Plaistow, NH · 5★ Google (165 reviews, 2026-06-03) · 100% five-star (157 of 157)

Carries the highest star rating in the Salem pack, a perfect 5.0 across 165 Google reviews (a clean 100 percent five-star on its rated breakdown of 157, June 2026), with a spotless BBB record (accredited 2025, 0 complaints in three years), based next door in Plaistow. It out-rates 603 on raw stars and is the closest competitor here, which is why we hold it as a clear second. It ranks below 603 only because it publishes no named system or transferable warranty terms, where 603 publishes both for a buyer to check in advance.

www.reliablebasementwaterproofing.net

Haverhill, MA (serves southern NH incl. Salem) · 5★ Google (32 reviews, 2026-04-05) · 100% five-star (32 of 32)

Third in the Salem pack with a perfect rating on a smaller base (5.0 across 32 Google reviews, June 2026), a Haverhill, MA full-service basement company (waterproofing, moisture control, finishing) with more than 20 years of work across New England that states it serves southern NH including Salem. A strong record, but on a much shallower review base than the two above, and it publishes no named system or transferable warranty.

northeastbasements.com

Also serving the area

Hudson, NH · 4.8★ Google (676 reviews, Yelp 3.3/19, 2026-06-03) · 92.3% five-star (624 of 676)

A family-owned Hudson firm and Basement Systems dealer with a complete waterproofing system, the deepest review base in the wider area (4.8 across 676) and a clean BBB record (A+, accredited 2015, 2 complaints in three years). It installs the national Basement Systems product line rather than a system of its own.

www.ericksonfoundations.com

National (HQ Virginia Beach, VA); nearest branch Hooksett, NH (formerly Rescon) · 4.9★ Google (567 reviews, 2026-06-03) · 95.6% five-star (542 of 567)

The national option, with a patented product line and a nationally backed warranty (4.9 across 567). It is a national consolidator (HQ Virginia Beach, VA; the Hooksett branch was formerly the independent firm Rescon) whose warranty service runs through the national company, and its corporate BBB profile shows 741 complaints closed in three years, about 69 percent of them service or repair.

www.groundworks.com

Side-by-side

CompanyTypeGoogle (June 2026)Named systemPublished warrantyBBB
603 Basement Solutionslocal independent4.9 / 250Forever Dry SystemPublishes a transferable "Dry for Life" guarantee (marketing wording; exact written terms pending).A+, BBB accredited since 2022
Reliable Basement Waterproofinglocal independent5 / 165NoneNo warranty terms published on its website (may be presented at quote).A+, BBB accredited 2025, 0 complaints (3yr)
Northeast Basement Solutionslocal independent5 / 32NoneNot stated on its website; ask at quote.Not assessed here
Erickson Foundation Solutionslocal national brand4.8 / 676Installs the national Basement Systems line (TripleSafe, SaniDry, WaterGuard) rather than a self-branded systemTransferable written warranty (duration not stated).A+, accredited 2015, 2 complaints (3yr)
Groundworksnational consolidator4.9 / 567Patented national product line (IntelliJack, AquaStop)Lifetime, transferable, nationally backed (verbatim terms not verified).A+ (corporate); 741 complaints closed in 3 years, 514 Service/Repair (~69%), per BBB national profile, accessed June 2026

Head-to-head comparisons

Other services in Salem & Derry, NH

Data verified as of the dates shown; star ratings change over time. See our methodology.