My phone #'s are in that format, and when using the app on my phone it already works the way you describe, tapping that field I have the option to call or text. Are you talking about having that ability in the web version?

On the desktop, you must have a call application. Google Voice has a free plan. I use the $10/ month plan. It makes all numbers callable from my desktop.notebook. The paid version of voice adds a couple of other features. 

When you say when using the app on my phone, are you referring to the Airtable app?

I'm looking for a solution that allows for users of my web app to click that field and be able to dial that number... 

I tried this solution but it didn't work for me...

Not really sure this applies to my question, but thanks for chiming in...

Yes that is what I referred to. I feel that the user would need a desktop application to call from a separate web app? But there is so much ability AT has I don't know....following to see if someone else as the answer you seek!

A call application is required on the desktop.  From my desktop or notebook, I can call all numbers. Other features are available in the paid version of voice. 

Maybe it was how I worded my question, but this problem has nothing to do with clicking on phone links within Airtable.

However, here's the solution that worked for me, just in case someone else is having a similar issue in the future:

1. Create a Formula field
2. Paste the following formula: 

Hope that helps!

What call system do you use? I use Google Voice Business for $10/mo.

Please provide an example of actual input and output.

It is not working for me, where are the links appearing for the users to click? in a gridview or interface?

1. 'Determine the RowIndex of the Row whose LinkButton was clicked. Dim rowIndex As Integer = Convert.ToInt32(e.CommandArgument)
2. 'Reference the GridView Row. Dim row As GridViewRow = GridView1.Rows(rowIndex)
3. 'Fetch value of Name. ...
4. 'Fetch value of Country.