Serial Number Guide
Last updated 1 January 2026
All eligible carbon credit units created within the BidCarbon Standard Scheme are assigned a unique serial number to eliminate double counting of units as well as to provide a pedigree for each unit created.
Eligible carbon credit units are issued to projects in “batches.” Each batch represents a quantity awarded to a single project for a specific reporting period. The table below identifies the serial number format that will be used by the BidCarbon Standard Scheme.
The requirement for a unique serial number shall take effect from 1 January 2026.
5
L1234
Batch Number
Number assigned to each batch of eligible carbon credit units created
Two-letter country codes in ISO3166, as of 01 January 2005
CN
Host country
2
15
Unit Serial Block End
Unique numeric values assigned by registry from 1 - 999,999,999,999,999
7
BSS123456
Project Identifier
Numeric value assigned by registry for Project, unique throughout the registries syste.
3
Unique numeric values assigned by registry from 1 - 999,999,999,999,999
6
15
Unit Serial Block Start
BRU
Unit Type
A6U=Article 6 BidCarbon removal unit
BRU=BidCarbon removal unit
4
1
2026
Vintage
Year in which the unit was issued
Display order
Example
Identifier
Range or Codes
Example
Start serial number:
2026-CN-BSS123456-BRU-L103-0
End serial number:
2026-CN-BSS123456-BRU-L103-102
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