Supporting information files (level 1 and 2)
Learn about our supporting information files (level 1 and 2) to help you validate your invoice.
What are supporting information files?
Supporting information files contain lower-level detail that support invoices.
Files used in first level of supporting information
The first level of supporting information comprises "thin files".
These are:
- mandatory to accompany core invoices (CAZ, COM and AMS)
- sent with some ancillary invoices
- automatically sent in a separate file and on the same day (as the .INV file)
- sent via Information Exchange (IX)
Files used in second level of supporting information
The second level of supporting information comprises "thick files".
These are:
- not mandatory and only available for core invoices (CAZ, COM and AMS)
- delivered via IX at a later date following invoice generation within agreed timescales
Second level supporting information files are available to Shippers upon request by completing our Request for Additional Supporting Information Template.
Request for Additional Supporting Information Template
Once completed, you should send this template to us by email.
Retrospective requests for supporting information
We don’t accept retrospective requests for supporting information as a standard service. However, you may email our Commercial team if you wish to make an exceptional request. You’ll need to set out the exact details of the information you need.
How supporting information relates to core transportation invoices
The table below provides an overview of how level 1 and level 2 supporting information relates to core transportation invoices.
| Core Invoice | Invoice | Supporting Information 1st Level | Supporting Information 2nd Level |
| COM | Commodity | COM | COI |
| CAZ | Capacity | ZCS | CZI |
| AMS | Amendment | ASP | AML |
Supporting information hierarchy
Supporting information follows a hierarchy. As an example, the capacity invoice supporting information (.ZCS) shown below is formatted into three levels.
Where to find file hierarchies and formats
You can find our supporting information file hierarchies and file formats in the UK Link Documentation Library secure area.
The relevant file format document also contains information on how to read the files.
If you don’t have access to the secure area, please visit Accessing secure documents.
Help centre – invoices
Need more help?
For more help with supporting information files, please raise a support request.
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