How can I populate today’s date on a date field only when not hidden with branching logic?

Create a date field, add @TODAY and @HIDDEN Action Tags. This is a hidden field which we will use to pipe today's date to another field.

Create a second date field and add @CALCTEXT:

@CALCTEXT(if([sui]='1',[today],'')) This says if the "sui" field response is "Yes", pipe the value from the "Today" field, otherwise, leave blank.

Reference the branching logic for the field and value as an if/then else statement

[sui]='1'   This says if field equals 1, pipe the value from the date_field to the 2^nd date field, otherwise leave it blank.

More information on using  CALCTEXT and other Conditional Logic can be found on the Help & FAQ page in REDCap

For additional assistance, please contact the REDCap Support Team