The option to allow a donation to be anonymous can be set on the Extras tab. This will add a checkbox below the Address information that a donor can mark if they wish to keep this anonymous:
Anonymous checkbox on Online Express donation form
If a donor marks this:
  • The page confirmation (what appears on the form after the gift is made) will add a note of "This gift will remain anonymous" below the transaction details. (This verbiage is part of the Transaction Details merge field.)
 
  • The email confirmation (emailed to the donor after the gift is made) will include a note of "This gift will remain anonymous" below the transaction details. (This verbiage is part of the Transaction Details merge field.)
 
Anonymous gift in Online Express Donation download
 
 
  • The gift, but not the constituent (seen on Bio1/Org1), will be marked as anonymous. For more information on anonymous settings in The Raiser's Edge, please refer to How to track anonymous donors and gifts