Hi Lexie,

To only  set the display format,you can find the answer on thread of the forum  :Can i format the number type in Nintex Forms seperate by ","

If you want to create a real validation you have to set the Regular expression in the validation part of your field, and set the error message associated. For your case, it's not really complicated. I just tested it :  :0-9]{4}.{0-9]{3}.{0-9]{4} (i tried several cases, it seems to work)

If you don't meet the correct format , it will prompt you an error .

Good luck

I have a similar question so I'll tack it on to this one.  I have a currency field that stores $0 if the user forgets the dollar sign so I want to use a regex to force the input of that character at the beginning of the string.  I've tried ^$ and ^ $], both of which work as expected in a regex tester (such as RegExr: Learn, Build, & Test RegEx ) but I still fail validation when I enter, say, $500.

This seems like a pretty simple case but it's not working. I even changed the column from currency to single line of text in case it was SharePoint rejecting the entry.

What am I doing wrong?

Thanks,

Bruce