ANAB Accreditation: What It Covers and How to Verify It

“ANAB accredited” appears on lab reports, calibration certificates, and vendor qualification packets constantly, but it is not a single, uniform claim. ANAB (the ANSI National Accreditation Board) accredits organizations against more than a dozen different ISO/IEC standards, across testing, calibration, medical, inspection, certification, and forensic programs, and a given accreditation always applies to a specific site, a specific standard, and a specific scope of methods — never to a company as a blanket guarantee. For a lab manager, procurement officer, or research administrator vetting a testing lab, calibration provider, or reference-material supplier, understanding exactly what an ANAB accreditation claim does and does not cover is what turns “they’re accredited” from an assumption into a verified fact.

This guide covers what ANAB is, what it accredits, how it compares to other US accreditation bodies, how to verify a supplier’s ANAB accreditation before you sign a contract, what the accreditation process and its costs actually look like, and how to use accreditation status as a real procurement criterion rather than a checkbox.

What Is ANAB?

ANAB, the ANSI National Accreditation Board, is a US-based accreditation body that evaluates and formally recognizes the technical competence of testing laboratories, calibration laboratories, medical laboratories, inspection bodies, certification bodies, and reference material producers against international ISO/IEC standards. ANAB itself does not test or calibrate anything — it accredits the organizations that do, meaning it independently assesses whether a lab’s staff competence, equipment, methods, quality system, and measurement traceability actually meet the requirements of the standard it claims to operate under.

ANAB traces its origins to a partnership between the American National Standards Institute (ANSI) and the American Society for Quality (ASQ), which combined their accreditation activities into a single organization; it has since operated as ANSI’s national accreditation body, now branded simply as the ANSI National Accreditation Board. ANAB is one of the largest accreditation bodies in North America and, like its peer bodies, is a signatory to international mutual recognition arrangements — the ILAC MRA (International Laboratory Accreditation Cooperation Mutual Recognition Arrangement) for laboratory and inspection accreditation, and the IAF MLA (International Accreditation Forum Multilateral Recognition Arrangement) for management-system and product certification — which is why an ANAB-accredited test report is generally accepted as equivalent to a report from a lab accredited by another ILAC MRA signatory body in a different country, without re-testing.

What ANAB Accredits: Standards and Scopes

ANAB is a multi-standard accreditor. The standard that matters for your evaluation depends entirely on what kind of organization you’re vetting:

• ISO/IEC 17025 — General requirements for the competence of testing and calibration laboratories. This is the standard behind most “ANAB accredited” claims from commercial and industrial testing labs, calibration houses, and environmental/materials/product testing labs. See CASRAI’s ISO/IEC 17025 guide for what this standard actually requires.
• ISO 15189 — Requirements for quality and competence specifically in medical laboratories. ANAB accredits clinical/medical labs under this standard as an alternative or supplement to CLIA certification and CAP accreditation.
• ISO/IEC 17020 — Requirements for bodies performing inspection (as opposed to testing) — e.g., equipment inspection, facility inspection.
• ISO/IEC 17065 — Requirements for product certification bodies.
• ISO/IEC 17024 — Requirements for personnel certification bodies (the standard behind accredited professional-credentialing programs).
• ISO/IEC 17043 — Requirements for proficiency testing (PT) providers — relevant when you’re sourcing PT/EQA samples for your own lab’s competency program. See CASRAI’s proficiency testing and EQA guide.
• ISO/IEC 17021-1 — Requirements for bodies certifying management systems (e.g., ISO 9001, ISO 14001, ISO 45001 certification bodies).
• Forensic testing — ANAB accredits forensic laboratories under ISO/IEC 17025 plus its own supplemental forensic requirements, historically covering the accreditation base built by the former ASCLD/LAB (American Society of Crime Laboratory Directors/Laboratory Accreditation Board) program, which ANAB absorbed.
• Food safety — ANAB accredits certification bodies operating under GFSI-recognized schemes such as FSSC 22000 and SQF.

The practical takeaway for procurement: “ANAB accredited” alone tells you almost nothing. “ANAB accredited to ISO/IEC 17025 for [specific test method]” or “ANAB accredited to ISO 15189” tells you something verifiable and actionable. Always ask which standard, and confirm the specific scope, rather than accepting the acronym on its own.

ANAB vs. Other US Accreditation Bodies

ANAB is not the only accreditor operating in this space, and procurement teams comparing suppliers often need to know how the major bodies relate rather than compete:

• A2LA (American Association for Laboratory Accreditation) — ANAB’s main peer/competitor for ISO/IEC 17025 testing and calibration lab accreditation in the US. Both are ILAC MRA signatories, and an accreditation from either body carries equivalent international standing under the MRA. A lab is accredited by one or the other, not both, for a given scope — the choice usually reflects the lab’s own history or the specific technical scopes each accreditor supports well, not a quality difference between the bodies themselves.
• CAP (College of American Pathologists) and CLIA — the dominant accreditation/certification pathways for US clinical laboratories specifically; see CASRAI’s CAP accreditation checklist and CLIA inspection checklist. A clinical lab may hold CLIA certification via CAP deemed status, or via ANAB’s ISO 15189 accreditation as an alternative deeming pathway — these are not the same audit and are not automatically interchangeable for every payer or regulatory purpose.
• The NELAC Institute (TNI) — the recognized standard-setting body for US environmental laboratory accreditation; ANAB is one of several accreditation bodies recognized to accredit environmental labs under the TNI/NELAP program.
• IAS (International Accreditation Service) — another ILAC MRA-signatory US accreditor, competing with ANAB and A2LA primarily in construction-materials and special-inspection testing.

For procurement purposes, the accreditor’s name matters less than confirming (a) it is genuinely ILAC MRA/IAF MLA-signatory-recognized, and (b) the specific scope of accreditation covers the exact test method, calibration parameter, or clinical assay you’re procuring against.

How to Verify a Supplier’s ANAB Accreditation Before You Sign

Treat an accreditation claim on a proposal, quote, or website the same way you’d treat any other unverified vendor claim — confirm it independently before it becomes a contract requirement. In practice:

1. Get the accreditation certificate number and search ANAB’s public accredited-organization directory (ANAB publishes a searchable database of currently accredited organizations). Confirm the organization is listed as currently accredited, not lapsed or suspended.
2. Pull the actual scope of accreditation document, not just the certificate. The certificate confirms accreditation exists; the scope document (sometimes dozens of pages for a large lab) lists the exact standards, test methods, measurement parameters, and ranges the accreditation actually covers. A lab can be genuinely ANAB-accredited and still not be accredited for the specific method or parameter you need — this is the single most common gap procurement teams miss.
3. Check the expiration/reassessment date. ANAB accreditation is not permanent; it runs on a defined assessment cycle (typically annual surveillance with a full reassessment cycle, commonly on a multi-year period depending on the program) and can be suspended or withdrawn for unresolved nonconformities.
4. Confirm the site address matches where the work will actually be performed. Accreditation is site-specific. A supplier’s headquarters being accredited does not mean a satellite location or subcontracted site is.
5. Ask how nonconformities from the last assessment cycle were resolved. Accreditation bodies require corrective action for findings but don’t publish the finding detail; a reputable supplier will discuss its own audit history. See CASRAI’s guide to nonconformities and the NCR/NCAR process for how major vs. minor findings are typically classified and closed.

This same verify-before-you-sign discipline applies to any ISO/IEC 17025 accreditation claim regardless of accreditor — see CASRAI’s companion guide, ISO/IEC 17025 Accreditation: How to Verify a Supplier Before You Sign, for a fuller walkthrough of the verification workflow.

The ANAB Accreditation Process

For a lab or organization pursuing ANAB accreditation (rather than buying from an already-accredited supplier), the process generally follows this sequence, common across ANAB’s programs:

1. Application and scope definition — the applicant defines exactly which standard, which test methods/calibration parameters or clinical assays, and which site(s) it wants accredited.
2. Document review — ANAB reviews the applicant’s quality management system documentation against the relevant standard’s requirements before scheduling an on-site visit.
3. On-site assessment — ANAB assessors, typically technical experts in the applicant’s specific field, conduct an on-site evaluation of personnel competence, equipment, method validation, measurement traceability, and quality-system implementation, not just paperwork.
4. Corrective action — findings (nonconformities) identified during assessment must be resolved and evidenced before accreditation is granted.
5. Accreditation decision and certificate issuance — once findings are closed, ANAB issues the certificate and publishes the scope of accreditation.
6. Ongoing surveillance and reassessment — accreditation is maintained through periodic surveillance visits and a full reassessment cycle; it is not a one-time achievement.

ANAB Accreditation Cost: What Drives It

ANAB, like other accreditation bodies, does not publish a single flat price for accreditation, because cost scales with the size and complexity of what’s being accredited rather than being a fixed fee. The real cost drivers procurement and lab-management teams should budget for:

• Application/administrative fees — a fixed fee to initiate the accreditation application, generally the smallest line item.
• Assessment fees, billed by assessor-day — the largest driver. The number of assessor-days required scales with the number of test methods or calibration parameters in scope, the number of physical sites, and the technical complexity of the field — a lab seeking accreditation for a handful of methods at one site costs meaningfully less to assess than a multi-site lab with dozens of scope items.
• Assessor travel and expenses — on-site assessments bill travel time and expenses separately from the assessor-day rate.
• Annual accreditation fees — a recurring fee to maintain accreditation once granted, separate from the periodic surveillance/reassessment assessment costs.
• Internal cost of readiness — the largest cost for most applicants is rarely the accreditor’s invoice; it’s the internal labor to build and document a compliant quality management system, validate methods, and prepare staff, often requiring outside consulting for a first-time applicant.

Because ANAB’s actual fee schedule varies by program and scope and is not a single published number, the reliable way to budget is to request a formal quote directly from ANAB (or, for buyers evaluating a supplier’s price, to ask the supplier how their ANAB accreditation costs are amortized into their pricing) rather than relying on a generic figure — scope size is the dominant variable, and two organizations with the same standard can have very different costs.

Why ANAB Accreditation Matters for Procurement

Accreditation status is a real, verifiable risk-reduction signal in a vendor evaluation — but only if it’s used as evidence to check, not a label to trust. A defensible procurement approach:

• Require the specific standard and scope of accreditation relevant to the goods or services being purchased as a contract or RFP condition, not just “must be accredited.”
• Verify the scope document against your actual technical requirement before award, not after a problem surfaces.
• Build periodic re-verification into supplier management — accreditation can lapse, be suspended, or have its scope reduced mid-contract; a one-time check at onboarding is not sufficient for an ongoing supply relationship.
• Where accreditation doesn’t yet exist for a needed scope (a specialty test method, a novel assay), evaluate the supplier’s documented capability and any interim proficiency-testing performance instead of treating “not yet accredited” as an automatic disqualifier, particularly for narrow or emerging technical scopes accreditors haven’t built assessor capacity for yet.

This is the same evidence-based standard CASRAI applies across its own accreditation-verification guides: an accreditation claim is a starting point for due diligence, not a substitute for it.

Frequently Asked Questions

What is ANAB?

ANAB (the ANSI National Accreditation Board) is a US accreditation body that evaluates testing, calibration, medical, inspection, and certification organizations against international ISO/IEC standards and formally accredits them once they demonstrate compliance. It is a signatory to the ILAC and IAF international mutual recognition arrangements, which gives ANAB-accredited reports international standing.

Is ANAB the same as ISO?

No. ISO (the International Organization for Standardization) writes the standards (ISO/IEC 17025, ISO 15189, etc.); ANAB is one of the accreditation bodies that independently verifies and certifies that a specific organization actually meets those standards at a specific site.

How much does ANAB accreditation cost?

ANAB does not publish a flat fee; cost depends primarily on the number of assessor-days required, which scales with how many test methods/parameters and sites are in scope, plus application and recurring annual fees. Request a scope-specific quote directly from ANAB rather than budgeting off a generic number.

Does ANAB accredit medical laboratories?

Yes, under ISO 15189, as an alternative or supplement to CLIA certification obtained via CAP or state survey. See CASRAI’s CLIA inspection checklist and CAP accreditation checklist for how the more common US clinical-lab pathways compare.

Is ANAB accreditation better than A2LA accreditation?

Neither is inherently “better” — both are ILAC MRA signatory accreditation bodies whose ISO/IEC 17025 accreditations carry equivalent international recognition. Procurement teams should evaluate the specific scope of accreditation a supplier holds, not which of the two accreditors issued it.

How do I check if a lab’s ANAB accreditation is still valid?

Look up the organization and certificate number in ANAB’s public directory of accredited organizations, and request the current scope of accreditation document directly from the supplier to confirm it covers the exact method or parameter you need and hasn’t lapsed or been reduced since issuance.