You may not think twice about the brand of the water filter you buy, but did you know that some water filters are counterfeits? Counterfeit filters may not reduce the contaminants they claim. According to a global survey commissioned by NSF International and conducted by an independent agency, 66% of consumers in nine countries are worried about counterfeit filters.

Because of their popularity and relatively high price, refrigerator filters are the most common counterfeits on the market, according to Rick Andrew of NSF International’s global water program.

Water Treatment Standards

The standard NSF/ANSI 53: Drinking Water Treatment Units – Health Effects sets minimum requirements for whole-house and point-of-use water filters. The standard makes sure that systems can effectively filter the specific contaminant they claim to filter, such as lead, cysts, volatile organic compounds (VOCs) and chromium. Another standard, NSF/ANSI 42: Drinking Water Treatment Units - Aesthetic Effects, sets minimum requirements for systems that reduce non-health-related contaminants that may affect taste, odor and color.

Water filters, fittings and all plumbing products that contact drinking water must be certified to NSF/ANSI standards, which establish minimum criteria for safety of the materials to be in contact with drinking water. Certification ensures products and their manufacturers meet minimum requirements through a seven-step process that includes reviewing product formulation and toxicology information; auditing production facilities; and conducting a series of laboratory tests. NSF certified products and packaging bear the NSF mark with specific reduction contaminant claims for that product.

Why You Should Avoid Counterfeit Filters

The main reason to avoid counterfeit filters is that they may not reduce the contaminants the manufacturer claims. Additionally, counterfeit filters may be constructed with unsafe materials that introduce potentially harmful compounds into the drinking water.

Other risks of counterfeit products include:

  • The fit may not be perfect, and they may become stuck inside the refrigerator.
  • Possible leaks and water damage from improperly fitting filters may occur.
  • Counterfeits cost additional money for repairs to damaged refrigerators and may void the manufacturer’s warranty.

What’s the Difference?

So how can you tell the difference between an NSF-certified filter and a counterfeit filter that may be similarly packaged and marked? Consider these tips.

  • Weight: Counterfeit filters often weigh less than certified filters because they lack the proper amount of materials that make them effective.
  • Certification symbol: Certification marks are likely to be small so they don’t attract as much attention or scrutiny.
  • Glossy packaging: Counterfeit filters might be packaged in boxes with a glossy finish to appear high-quality.
  • Cost: Counterfeit filters usually cost significantly less than authentic certified filters.

When in doubt, check out NSF International’s official list of certified filters or contact the NSF consumer information hotline at +1 (800) 673-8010 or