Billing CDR Standard and Examples

For our CDR files we aim to match the FCS 3.01 specification as closely as possible.

Please see here for the full specification: UK-Standard-CDR-Format-v3_01-Final

Note that whilst we do our best to match FCS 3.01, some aspects are not implemented.

Phone Number Format

All phone numbers in the CDR are in E.164 format. This can be shown as:

+(Country Code)(Rest of Phone Number)

For example, the UK phone number 0333 188 7878 in E.164 format would be +443331887878.

CSV Format

All CDR files will be downloaded as a CSV file. Due to the specific formatting requirement of the file it is highly recommended that you do not open the CDR file in spreadsheet software (such as Excel) as these programs will likely automatically change the formatting when you open them (for example they will likely remove the "+" at the start of phone numbers), which will cause billing engines to fail to read it correctly.

If you do want to open and read your CDR record, please make a copy of it first.

Diverted Calls

If a call is diverted, it will show on the CDR as two separate lines. One of the inbound side of the call, and the other for the outbound. You can tell which is which via the "RecordID" column, in which the inbound side of the call will be prefixed with "DIVERTED_INBOUND_" and the outbound side with "DIVERTED_OUTBOUND_"

Example CDR File

See below to download an example of what our CDR files look like.

Access4 - CDR Example File 03_11_2025

File Breakdown

See below for a full breakdown of the standard and how we implement each column.