post https://api-sandbox.cv.gpsrv.com/intserv/4.0/setRoundupAccounts
Use the Set Roundup Accounts endpoint to specify the roundup account for a consumer account, such as rounding up into a charity account. (To enable roundup for the account, call Set Account Feature with type: 11.) You can assign multiple roundup accounts to a single consumer account. The total percentage from all linked roundup accounts must equal 100.
See Global Response Statuses for status codes that are common across endpoints.