Formula to show a field if another is empty

It looks like this works:

IF(
  AND(
    Phone,
    {Phone Extension}
  ),
  IF(
    Phone,
    Phone,
    {Phone Extension}
  ),
  IF(
    Phone,
    Phone,
    {Phone Extension}
  )
)

Strangely this shows an error:

IF(
  AND(
    Phone,
    {Phone Extension}
  ),
  IF(
    Phone,
    'tel://' & VALUE(Phone),
    'tel://' & VALUE({Phone Extension})
  ),
  IF(
    Phone,
    'tel://' & VALUE(Phone),
    'tel://' & VALUE({Phone Extension})
  )
)

Not sure what I’m doing wrong?
All I want to do is prefix the raw value with tel://

Welcome to the community, @gmclelland! :grinning_face_with_big_eyes:

This logic is a bit odd. If both exist, then there’s no need to test again to see if {Phone} exists because its presence is already assured by passing the “if both exist” test.

I was able to simplify your formula, and get the “tel://” prefix to work. Here’s what I came up with:

IF(
    OR(Phone, {Phone Extension}),
    "tel://" & VALUE(IF(Phone, Phone, {Phone Extension}))
)

If either {Phone} or {Phone Extension} exist, the formula starts with the “tel://” prefix. To that prefix, it will add the value of either {Phone} or {Phone Extension}, with {Phone} taking priority by being tested first. By the time that inner test arrives, the formula knows that one of the two is there, so it’s a simple process of elimination. If the initial OR() test fails, then nothing else happens.

Notice that the {Phone} field is the phone number field type, and “Phone Extension” is single line text. My gut says that one of those two fields is a number field in your base. If so, that explains the error. The VALUE() function requires a string, and throws an error if you feed it a number.

@Justin_Barrett, One other related question:

If I take your working formula and put it into a button field, even if the field doesn’t contain any values it will still show a greyed out button.

Is there anyway to remove the greyed out buttons?

My ultimate goal was to have a “Call with GoToConnect” button for users to be able to click to call with their phone.