Saltar al contenido

Working with others

When your supplier subcontracts someone else

Documents start arriving in the name of a company that is not in your contract. What to do with them.

Updated on 13/08/2026

You hired one company and suddenly the delivery note comes from another, the technician who turns up wears a different logo, or the certificate arrives in a third party's name. It is neither rare nor necessarily a problem — it becomes one when it happens with nobody saying so and the documents come in anyway.

What changes and what does not

AspectWhat happens when there is a subcontractor
Who answers to youThe company you hired, unless you agreed otherwise
Who produces the documentsIt may be the other one, and usually is
Who you claim againstYour supplier, not whoever carried out the work
What you must be able to showThat you knew who was working and with what documentation

Important

The fourth row is the neglected one and the one anyone reviewing asks about: **a document in the name of a company that does not appear in your contract says nothing on its own**. With no record that this third party was authorised by your supplier to do that work, you hold a certificate that cannot be tied to anything. And it cannot be fixed later, because what is missing is the link between the two, not the paper.

How to tie it down without slowing the work

  1. 1

    Ask them to notify the subcontracting

    An email from the supplier saying who they delegate to and for what is enough.

  2. 2

    Keep that email in the same file

    It is the piece that links the document to your contract.

  3. 3

    Ask the subcontractor for what you ask the supplier

    Through the same process: no need to invent a new one.

  4. 4

    And note the date from which they are involved

    If something happened before or after, that date settles it by itself.

Watch out

The most surprising part of this situation: **whoever has to ask the subcontractor for documents is usually your supplier, not you** — it is their relationship, not yours. Yet whoever answers for not having them, when someone reviews, is still you. That asymmetry is uncomfortable and it is real, and it is handled by asking your supplier: let them hand the documents over, even if someone else produced them.

When it is worth stopping

Worth knowing

How far you are required to control the chain depends on the sector and the type of work, and some have specific subcontracting rules. **Your adviser settles that**; what matters here is that traceability of who did what is lost at the first link nobody wrote down.

Can I forbid subcontracting?

That is a contract clause, and your adviser will tell you how to word it.

What if I find out by chance?

That is the signal to ask for it in writing, not that there is bad intent.

Do I give the subcontractor access?

Better that they contribute the same way any third party does, with their own trace.

A real case

The situation

A company receives certificates in the name of a firm that is not in its contract.

What you do

  1. Asks its supplier for the email authorising the subcontractor and files it alongside

What you get

The certificate is linked to the contract, and the review no longer has a loose end.

The situation

Your maintenance supplier sends a different company and nobody knew until the van arrived.

What you do

  1. Agrees contractually whether they may subcontract and on what terms
  2. Records which firms are authorised for each supplier
  3. Requires of the subcontractor what is required of the supplier

What you get

The chain is known before the job and the documentary gap does not sit on your balance sheet.

The situation

The client asks about the subcontractor and nobody knows who they are.

What you do

  1. Asks the supplier to declare their chain

What you get

The answer exists before the question.

The situation

The subcontractor does not meet what the supplier signed.

What you do

  1. Passes the same list down the chain

What you get

The commitment reaches whoever executes.

The situation

Subcontracting is authorised verbally.

What you do

  1. Records it with its scope and date

What you get

What was authorised is demonstrable.

The situation

The subcontractor changes and nobody communicates it.

What you do

  1. Asks to be informed of any change

What you get

The change arrives before the job.

The situation

A review asks who was on the premises on a specific day.

What you do

  1. Checks the record of authorised access

What you get

You answer using that day's date.

The situation

The subcontracting is discovered during an audit.

What you do

  1. Reviews the declared chain periodically

What you get

The finding is made before the auditor makes it.

This article answers

  • my supplier has subcontracted another company
  • a certificate arrives from a company I do not know
  • who answers if the subcontractor fails
  • supply chain documentation