AS9110 vs AS9120: A Clear Guide to Which You Need (2026)

Last updated 19 September 2026

AS9110 vs AS9120 is the question an aerospace organisation asks when it has realised that AS9100 does not describe what it does. The IAQG’s 9100 series has three quality management system standards on the same ISO 9001 base, each for a different position in the supply chain: AS9100 for organisations that design, develop and manufacture aviation, space and defence products; AS9110 for maintenance, repair and overhaul organisations working on aircraft and their components; and AS9120 for stockists and distributors that buy parts and sell them on without altering them.

The three share clauses 4 to 10, the certification scheme, the OASIS database and the authenticated auditors — and differ in the requirements inserted into the ISO 9001 text, because a repair station’s risks (technical data, tooling, release to service, human error) and a distributor’s risks (traceability, splitting, storage, counterfeit parts) are not a manufacturer’s. This guide sets the two apart on scope, structure and the requirements each adds, shows how to decide which applies to a mixed organisation, and explains what the pending IA-series revision changes for both.

AS9110 vs AS9120 at a glance

AS9110 vs AS9120 on the maintenance side: what AS9110 adds

AS9110 takes AS9100’s aerospace additions and replaces the manufacturing-specific ones with maintenance-specific ones. The requirements that distinguish it:

• Safety policy and human factors. Top management’s commitment extends to safety; human factors — the conditions that lead people to err, from fatigue to communication — are addressed in planning, training, corrective action and the analysis of maintenance errors.
• Technical data. Maintenance is performed to approved data — manuals, service bulletins, airworthiness directives, repair schemes — and the organisation controls its currency, availability at the point of work and the use of any data it develops itself.
• Competence and authorisation. Personnel who inspect, certify and release maintenance are qualified, authorised and recorded; the authorisation is the licence to sign.
• Tooling and equipment. Control of tools, test equipment and calibration, including tools loaned or customer-supplied; tool control for FOD prevention.
• Release to service. The maintenance release — the certification that work was performed in accordance with approved data by authorised persons — is the product; the QMS controls who may issue it and on what evidence.
• Work transferred and contracted. Maintenance subcontracted to others is controlled to the same standard, with the release chain intact.
• Counterfeit and unapproved parts. Suspected unapproved parts, not only counterfeits, are the risk in maintenance; 8.1.4 is applied with that scope.
• Safety management linkage. Rev C aligned the standard with safety management system concepts, so that the QMS and the SMS the regulator expects reinforce rather than duplicate each other.

AS9110 vs AS9120 on the distribution side: what AS9120 adds

AS9120 assumes the organisation adds no value to the part except availability, and builds its requirements around keeping the part and its identity intact from the manufacturer to the customer:

• Traceability. Every part traceable to its original manufacturer through certificates and the unbroken chain of custody; records retained for the periods customers and regulations require.
• Splitting and repackaging. Where a lot is split, the identity, traceability and certification of each portion is preserved, with controlled procedures and records.
• Storage, preservation and shelf life. Environmental conditions, shelf-life control, segregation of nonconforming or suspect stock, protection against damage and deterioration.
• Counterfeit and suspect parts. 8.1.4 applied to a business whose whole exposure is sourcing: approved-source policy, verification at receipt, quarantine and reporting.
• Certificates of conformance. What the distributor’s own certificate may state, and that it does not misrepresent the manufacturer’s.
• Control of external providers. The suppliers are the product; approval, monitoring and the flow-down of customer requirements are the core process.
• No processing. The distributor does not alter the part; work beyond splitting, kitting and repackaging takes the organisation outside AS9120’s scope.

Our guide to counterfeit parts prevention covers the process that is central to AS9120 and present in all three standards.

Deciding between AS9110 and AS9120 — or AS9100

The certification body agrees the standard and scope before the audit, and OASIS records which standard each certificate is issued against, so a mismatch is visible to every customer who checks. Our guide to AS9100 vs ISO 9001 covers the manufacturing standard the two variants branch from; AS9100 certification cost covers the fixed audit days that apply to all three.

AS9110 vs AS9120 after the IA-series revision

The IAQG’s renaming applies across the family: AS/EN/JISQ 9110 and 9120 become IA9110 and IA9120, rebased on ISO 9001:2026 alongside IA9100 and targeted for the same late-2026 publication, with a transition period the IAQG will confirm on release. The published key-change themes — expanded product safety, counterfeit parts and sub-tier control, quality culture and ethics, an APQP link — land differently in each: counterfeit parts and sub-tier control weigh on distributors; product safety, culture and human factors on maintenance organisations. Until publication, Rev C and Rev B remain the certifiable editions. Our guide to IA9100 tracks the revision.

Frequently asked questions

What is the difference in AS9110 vs AS9120?
AS9110 is the aerospace QMS standard for maintenance, repair and overhaul organisations, adding requirements on technical data, tooling, authorised release personnel, human factors and safety; AS9120 is the standard for distributors and stockists, adding traceability, splitting, storage, counterfeit-part and certificate controls and excluding design and manufacturing. Both contain ISO 9001:2015 in full.

Can a distributor certify to AS9100 instead?
It can, but AS9120 is the standard written for its activity and the one customers expect on a distributor’s certificate. A distributor that performs manufacturing or processing beyond splitting, kitting and repackaging has left AS9120’s scope and needs AS9100.

Does AS9110 replace FAA Part 145 or EASA Part-145 approval?
No. The regulatory approval is the licence to perform maintenance; AS9110 is the quality management system around it. Most repair stations hold both, and customers and primes require the AS9110 certificate on top of the approval.

Are the audits different?
The scheme is the same — IAQG ICOP, AS9104/1 audit days, authenticated aerospace auditors, results in OASIS — but auditors are authenticated for the standard they audit, and the audit tests the variant’s specific requirements.

What happens with IA9110 and IA9120?
They follow IA9100: renamed, rebased on ISO 9001:2026, targeted for late 2026 with a transition period announced on publication. Rev C and Rev B remain certifiable until then.

Where this leaves you

Settle AS9110 vs AS9120 by what the organisation does to the part: if it repairs, overhauls or modifies under an airworthiness approval, AS9110; if it buys and resells without altering, AS9120; if it manufactures, AS9100 — and where it does more than one, more than one scope on the same system. The ISO 9001 core and the IAQG scheme are shared; the inserted requirements are what the certificate actually says about you.

References

• IAQG — International Aerospace Quality Group — The 9100 series — 9100, 9110 and 9120 — the ICOP scheme and OASIS.
• IAQG — IA9100 Key Changes, clause view — The series overview (9100, 9110 Maintenance, 9120 Distributors) and the revision themes.
• SAE AS9102 — Aerospace First Article Inspection Requirement — The production process verification standard AS9100 invokes and AS9120 does not.

More on AS9100

• AS9110 vs AS9120 — you are here
• Aerospace quality management: the AS9100 family
• AS9100 vs ISO 9001
• Counterfeit parts prevention under 8.1.4
• AS9100 certification cost
• IA9100: the 2026 revision

The quality manual with the AS9100, AS9110 and AS9120 variants marked, the maintenance and distribution procedures, the traceability and splitting records, the tool control and technical data procedures and the counterfeit parts process are in the AS 9100/9110/9120 Aerospace QMS Toolkit, or start with the free templates.