Hello Johan,  API is following the properties that have been set in the FInancials ERP with Segment Keys(Module) / Number Series (ScreenId=CS202000) therefore we're currently unable to separate used numbering series based on where we realize our transactions. But soon we'll have a new feature implemented to API in 8.25 Version where we'll be able to override numbering series have been set in the Financials ERP while sending transactions via API. (In the first phase, this will be available with particular endpoints. Details can be seen at Visma.net Financials API updates for version 8.25 (September 2020) ) Regarding, finding out the recently created object's Number / ID, this can be retrieved by checking the value of {Location} from HTTP Response Headers.       HttpResponse.GetResponseHeader("location");         ... View more