How do I include extensions in the tel: URI? - html

Question

I currently have a webpage serving up phone numbers, some of these phone numbers have extensions so I have written the HTML like this:
[phone] / <a href="tel:[phone];ext=99">[phone]</a
When I hit this page in my Android browser and tap one of the phone numbers, it loads up in my phone dialer (UK Samsung Galaxy s2 stock) as:
[phone];ext=88
which I don't think is correct. Surely it should omit the ;ext= word.
Have I misread the RFC for implementing tel?

Answer 1

Seems the proper way to do it is use a comma:
[phone] ext.88
Just tested with iPhone and Android OS 2.1. Using ;ext=88 converts the ext bit into a number that is dialed with the extension (so it dials something like 35888 instead of 88).

Answer 2

Comment for How do I include extensions in the tel: URI?
As of June 2021 the RFC3966 ;ext= syntax still isn't implemented by Android, and it's inelegantly implemented by iOS.
Using ;ext=123 as an example:
Android: after the call connects a modal window appears asking Send the following tones? 396123 with No and Yes buttons. "Send the following tones?" is a precise technical description of what will happen if the user taps Yes, but it is probably not the best wording for the average user.
Android converts ;ext=123 into 396123 because it treats the letters the same way as if you were dialing something like 1-800-FLOWERS, and this is a broken implementation of the syntax.
iOS provides an option to the left of the Disconnect button that says Dial “ext=…”. When you tap on this "button" it will dial the extension number. This is inelegant and has bad usability because the "button" doesn't look like a button — it's just plain text — and because you can't see the extension number.
In addition, when you first tap on a phone link in iOS it presents a button at the bottom of the screen which partially rewrites the phone number into a local format, but which also preserves most of the ;ext= syntax, e.g. Call [phone];ext123. This is also inelegant, and it's ugly besides.
If you instead use just a ; which is supposed to mean "wait," as in "wait until the auto attendant message ends and then automatically dial the extension":
iOS: tapping the link displays a button stating Call [phone];123 which is slightly less ugly than the button described above.
iOs provides the same extension-dialing "button" described above except the extension number is visible, e.g. Dial “123”. It still has the other usability problems.
iOS does not automatically dial the extension after the message ends.
Android: after the call connects a modal window appears asking Send the following tones? 123 with No and Yes buttons.
Android does not automatically dial the extension after the message ends.
So for now, as of June 2021 it seems that the only way to include extensions in tel: links that will actually work is to use either ; for "wait" or , for "pause":
555-555-5555 ext. 123 — this will provide a UI component which the user can invoke to dial the extension. The usability of the UI component depends on the OS; neither are great, but Android's is arguably better.
555-555-5555 ext. 123 — this will automatically dial the extension a couple seconds after the call connects. Note: This mechanism will not work with voicemail systems that don't accept user input until the auto attendant message ends.

Answer 3

According to the documentation, you can add what you want like so 12345678;ext=123
See RFC 3966

Answer 4

In all the examples I saw, the value of ext is contained in the full number. So try including 88 in the href value:
[phone]

Answer 5

For those still wondering about this problem: I've found it best to use this format:
<a href="tel:[phone];22">

Answer 6

Standards at thenewcode from 3 months ago suggest using a microdata pause.
<a href="tel:[phone]p22">
Related:
Different standards persist across different external platforms and may change the processing of URIs. Click to call
features on Google Developers docs do not specify
Example:
Office's Skype uses x to represent extension within skype.

Answer 7

I feel like this is kind of a cop-out answer, but if this is not implemented consistently across devices yet, probably best to just not include the extension and let people dial it by hand:
[phone] ext. 88
or
[phone] ext. 88
Better to make the user do more work than to send 1/2 your users to the wrong extension.

Answer 8

I don't get the answers to this question - I think the're wrong. The correct link would look like this:
[phone] ext. 88