CDS is the new flexible, modern HMRC customs system replacing the 30 year old paper based CHIEF customs system.
It's how you will make import customs declarations from the end of September 2022.
CDS uses data processing rules and Union Customs Code (UCC) rather than paper based rules and community customs code (CCC).
You must use the new CDS tariffs rather than the CHIEF tariffs. If you use the wrong code, it will be rejected.
Traditional CPC codes have been enhanced for CDS. Check the tariff for your new procedure code.