AS9100 vs AS9120: Which One Do You Actually Need?

If you’re entering the Aerospace supply chain, one of the first questions you’re likely to face is straightforward on the surface:

Do we need AS9100 or AS9120?

It’s a common point of confusion.

On paper, the distinction looks simple. In practice, it often isn’t - and choosing the wrong standard can lead to unnecessary work, delays in certification, and missed opportunities with customers.

Understanding the difference properly is not just about compliance. It’s about positioning your business correctly within the aerospace supply chain.

The Core Difference

At a high level, the distinction between the two standards is based on the role your business plays.

AS9100 applies to organisations that manufacture, produce, or work on Aerospace products.

AS9120 applies to organisations that store, distribute, or resell Aerospace parts.

That is the starting point, and in many cases it is enough to make a decision.

However, aerospace supply chains are rarely that clean, which is where confusion begins to emerge.

Where AS9100 Applies in Practice

AS9100 is designed for organisations that are directly involved in the production or alteration of aerospace products.

This typically includes businesses carrying out machining, fabrication, assembly, or special processes such as coating or heat treatment. In some cases, it also applies to organisations responsible for design and development.

If your business is physically changing a product - whether by manufacturing it, modifying it, or applying a controlled process - AS9100 is generally the expected standard.

The emphasis is on maintaining control over how products are created and ensuring that what is delivered is consistent, traceable, and safe for its intended use.

Where AS9120 Applies in Practice

AS9120 is specifically designed for distributors.

These are organisations that hold, manage, and supply Aerospace parts without altering them.

Their role is not to manufacture, but to maintain the integrity of products as they move through the supply chain.

Rather than controlling how a product is made, the requirement is to ensure that it remains identifiable, traceable, and protected from damage, deterioration, or substitution.

This includes managing documentation, controlling storage conditions, monitoring shelf life, and preventing the introduction of counterfeit or suspect parts.

For businesses operating purely in this space, AS9120 provides the appropriate framework.

Where Businesses Get Caught Out

The difficulty arises with organisations that sit somewhere in between.

Many businesses do not fall neatly into a single category.

They may primarily distribute parts, but also carry out additional activities such as kitting, inspection, or light modification. In some cases, they may perform minor processes that do not feel like “manufacturing,” but still alter the product in a way that introduces risk.

This is where assumptions can cause problems.

From an internal perspective, the business may see itself as a distributor.

From the perspective of a customer - particularly a Prime or Tier 1 supplier - the expectation may be different.

In these situations, the required standard is often driven less by how the business sees itself, and more by how it is viewed within the supply chain.

How to Decide Properly

In Aerospace, certification is rarely a matter of preference, it is dictated by customer expectations.

The most reliable way to determine which standard applies is to step back and consider a few key questions.

Are you manufacturing or altering products in any way?

Are you purely storing and distributing parts?

What are your customers asking for, and what is required to become an approved supplier?

If a customer specifies AS9100, that requirement effectively overrides internal interpretation.

The supply chain defines the expectation, and aligning with that expectation is essential if you want to secure and retain work.

Can a Business Have Both?

In some cases, yes.

Organisations that operate across multiple activities - for example, manufacturing certain products while distributing others - may require both AS9100 and AS9120.

This is also more common in businesses with separate divisions or those expanding into new service areas.

However, for the majority of organisations, one standard will clearly apply once their role in the supply chain is properly understood.

The Risk of Getting It Wrong

Selecting the wrong standard is not just a technical issue.

It can lead to delays in certification, unnecessary rework within the management system, and confusion during audits. More importantly, it can signal to potential customers that the business does not fully understand its position within the Aerospace supply chain.

In an industry built on trust and control, that perception can be difficult to recover from.

Final Thought

The choice between AS9100 and AS9120 is not really about standards.

It is about clarity. Where does your business sit within the Aerospace supply chain, and what level of control do your customers expect from you?

Once that is understood, the answer becomes much more straightforward.

This is a decision point we deal with regularly at Vaelo Aerospace - helping businesses understand their position, avoid unnecessary work, and move forward with the right standard from the outset.