🔥 NADCAP
NADCAP Accreditation and CNC Machining: What It Really Covers
Here is the honest truth most directories will not tell you: NADCAP does not accredit CNC machining in the way buyers assume. NADCAP accredits special processes, the heat treat, the anodize, the nondestructive testing that often happen around machining, and only added a Conventional Machining program relatively recently. Understanding that distinction is the difference between sourcing intelligently and chasing a credential that may not apply to the cut you actually need.
NADCAPAS9100ISO 9001
NADCAP, the National Aerospace and Defense Contractors Accreditation Program, is run by the Performance Review Institute (PRI) on behalf of the prime contractors who make up the program. Its purpose is to standardize and audit the special processes that are hardest to verify by inspecting the finished part: heat treatment, chemical processing and coatings, welding and brazing, nondestructive testing, materials testing, surface enhancement like shot peening, and similar. For these processes, the aerospace primes pool their oversight into one rigorous accreditation rather than each auditing every supplier separately.
Plain CNC machining historically sat outside NADCAP because dimensions can be verified directly with a CMM, so it did not need the special-process treatment. PRI later introduced a Conventional Machining (CMSP) program, but it remains far less universal than the special-process accreditations, and not every prime requires it. This is why a buyer should be precise: if you are sourcing pure milling and turning, the credential you usually want is AS9100 for the quality system, with NADCAP applying to any special process the shop performs.
The upshot is that a shop advertising NADCAP for CNC machining is making one of two statements. Either it holds NADCAP for in-house special processes adjacent to its machining, which is common and valuable, or it holds the newer Conventional Machining accreditation specifically, which is rarer. Knowing which one matters before you assume coverage.
When a Machining Shop Genuinely Needs NADCAP
The clearest case is a shop that performs special processes in-house. If your machined titanium or stainless part is heat treated, anodized, passivated, or shot peened at the same facility, the aerospace prime almost certainly requires that specific process to be NADCAP accredited, even though the machining itself may only need AS9100. A shop that mills the part and then runs an in-house heat treat line without NADCAP on that line is a flow-down problem for an aerospace program.
The second case is the Conventional Machining (CMSP) accreditation itself, which a growing number of large primes are beginning to flow down for critical machined hardware. If your customer specifically calls out NADCAP machining, confirm they mean CMSP and that the supplier holds it, because it is a distinct accreditation with its own audit checklist covering setup control, tooling, in-process verification, and operator qualification.
For most commercial and even many aerospace machined parts, you do not need NADCAP on the machining and should instead verify NADCAP on the special processes in the routing, whether performed in-house or at sub-tier processors. Requiring NADCAP machining where it is not flowed down simply shrinks your supplier base for no benefit.
Verifying NADCAP Through eAuditNet and Reading the Scope
NADCAP accreditations are highly verifiable because PRI publishes them in eAuditNet, the program's online system. You can confirm a supplier's accreditations there, including which specific commodities and processes are accredited and the accreditation status and expiry. This makes NADCAP one of the more trustworthy credentials to check, provided you read the scope rather than the headline.
Read the accreditation line by line. A supplier may be NADCAP accredited for heat treatment but not for chemical processing, or for one welding method but not another. For machining specifically, confirm whether the accreditation is Conventional Machining or whether the listing is actually for an adjacent special process. The common error is seeing the NADCAP logo and assuming it blankets everything the shop does; it never does.
Also note that NADCAP accreditation is typically merit-based: well-performing suppliers earn longer accreditation intervals, while those with audit findings are reaudited sooner. A short interval or a recent finding is not disqualifying, but it is worth understanding. Cross-check the eAuditNet record against any certificate the shop shows you, and trust the database over the paper.
What This Means for Your Documentation and Sub-Tier Flow-Down
When special processes in your part's routing are NADCAP accredited, you should receive process certifications referencing the applicable specification, for example a heat treat cert to AMS 2759 for the relevant alloy, a passivation cert to AMS 2700, or an NDT report to the called-out method and acceptance class. These certs should trace to the lot and reference the NADCAP-accredited processor. The machining shop, as the integrator, is responsible for collecting and flowing these up to you.
If the machining shop outsources its special processes, its quality system under AS9100 must control those sub-tier processors and verify their NADCAP status, accreditation that you can independently confirm in eAuditNet. A clean defense or aerospace package therefore weaves together the machining shop's AS9100 quality system, the NADCAP accreditation on each special process, and full material and process traceability.
The practical buyer move is to map your part's routing first, identify every special process, and confirm NADCAP on each one specifically, rather than asking a machining shop for a blanket NADCAP that may not exist or may not cover what you think.
Frequently Asked Questions
Mostly not in the way buyers expect, and this trips up a lot of sourcing. NADCAP was built to accredit special processes that cannot be fully verified by inspecting the finished part: heat treatment, chemical processing and coatings, welding, nondestructive testing, materials testing, surface enhancement, and the like. Conventional CNC machining was historically excluded because dimensions can be measured directly, so it did not need special-process oversight. The Performance Review Institute later added a Conventional Machining (CMSP) program, but it is far less universal than the special-process accreditations and not every prime flows it down. So when a shop says it is NADCAP for CNC machining, you need to find out whether it means it holds the newer CMSP accreditation specifically, or whether it holds NADCAP for special processes it performs in-house alongside machining. For most machined parts the relevant quality credential is AS9100, with NADCAP applying to any special process in the routing. Always read the eAuditNet scope rather than assuming the logo covers the cut.
Yes, almost certainly, on those specific processes if the part is aerospace or defense hardware. Heat treatment and anodizing are exactly the kind of special processes NADCAP exists to control, because you cannot reliably verify a correct heat treat or a sound anodic coating just by measuring the part afterward. Aerospace primes flow down NADCAP requirements for these processes whether they are performed in-house at your machining shop or at a sub-tier processor. So the question is where the processing happens. If your CNC shop heat treats and anodizes in-house, those in-house lines need NADCAP accreditation for heat treatment and chemical processing respectively, and you should confirm each in eAuditNet. If the shop outsources them, the outside processors need the NADCAP accreditation, and the machining shop's AS9100 system must control and verify those sub-tiers. You should receive process certs referencing the controlling specifications, such as AMS 2759 for heat treat and AMS 2470 or the relevant spec for anodize, traceable to the accredited processor and the part lot.
Use eAuditNet, the Performance Review Institute's online system, which publishes NADCAP accreditations. You can look up a supplier and see exactly which commodities and processes are accredited, the status, and the expiry. This makes NADCAP one of the more reliably verifiable credentials, but only if you read the scope carefully rather than trusting the logo. A supplier might be accredited for heat treatment but not chemical processing, for one NDT method but not another, or for an adjacent special process while not holding Conventional Machining at all. Map your part's routing, list every special process, and confirm each one is accredited and current in eAuditNet. Watch the accreditation interval too: NADCAP is merit-based, so strong performers earn longer intervals between audits while suppliers with findings get reaudited sooner. A short interval or a recent finding is not automatically disqualifying, but it tells you something about the supplier's track record. Cross-check the database record against any certificate the shop shows you and trust the database when they disagree.
They are not competing credentials; they cover different things and a serious aerospace machining supplier needs both where applicable. AS9100 certifies the shop's overall quality management system, the configuration control, traceability, counterfeit prevention, FOD control, and first-article inspection that govern how the shop runs every job, including the machining. NADCAP accredits the individual special processes, the heat treat, plating, welding, and NDT, that AS9100 does not itself qualify. For the machining itself, AS9100 is the foundational requirement on most programs, and you verify it through the aerospace OASIS database. For any special process in the part's routing, NADCAP is the requirement, verified through eAuditNet. So the right framing is: AS9100 for the system and the machining, NADCAP for the special processes. If your part is pure milling and turning with no special processes, you likely need AS9100 and not NADCAP. If it involves heat treat or finishing, you need AS9100 on the machining shop and NADCAP on those processes, in-house or sub-tier.
Last updated: July 2026
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