Use ‘chunks’ of digits to help people read telephone numbers

Break telephone numbers into shorter blocks of digits or ‘chunks’.

Telephone numbers are easier to read when their digits are chunked, rather than written in one large group.

Australian telephone numbers in general use have no more than 10 digits:

• Landlines – 2 digits for the area code followed by 8 digits for the rest of the telephone number.
• Mobiles – 10 digits (there is no area code).

There are also categories of telephone numbers that don’t have 10 digits – for example, ‘13’ numbers have 6 digits.

Put a non-breaking space between the chunks of digits

Use a non-breaking space between chunks of digits in a telephone number. A non-breaking space means that line breaks won’t split up the number. The telephone number will stay together on one line.

You can insert a non-breaking space using the Unicode character U+00A0.

In HTML, use the entity   to insert a non-breaking space. You can also use the keyboard shortcut Ctrl+Shift+Spacebar in Word.

Write telephone numbers in the national or international format

Write telephone numbers in a format appropriate for the location of the users.

National format for telephone numbers

Use Australia’s national format when writing Australian telephone numbers for content that will be used within Australia.

For landline telephone numbers, write the 2-digit area code followed by a non-breaking space. Then write the rest of the number in 2 chunks of 4 digits.

Write mobile telephone numbers in 1 chunk of 4 digits and then 2 chunks of 3 digits.

International format for telephone numbers

Use international format for content that will be used outside Australia.

The international format uses a plus sign ’+’ to represent the international prefix, followed by a country code (‘61’ for Australia).

For landline numbers:

• start with a plus sign ‘+’ and add the country code (‘61’ for Australia)
• add the area code without the ‘0’
• write the telephone number in 2 chunks of 4 digits.

For mobile numbers:

• start with a plus sign ‘+’ and add the country code (‘61’ for Australia)
• omit the first ‘0’
• write the telephone number in 3 chunks of 3 digits.

Always write foreign telephone numbers in the international format.

Make telephone numbers accessible through ‘click-to-call’ functionality

‘Click-to-call’ allows users to call a telephone number by selecting (clicking) the number shown in content. When the user selects the number, the user’s mobile phone, other mobile device or personal computer (if it has a supporting application) calls the number.

Click-to-call makes telephone numbers more accessible because users don’t need to copy the number manually. Click-to-call also works with screen readers.

Devices sometimes recognise when a number in content is a telephone number and automatically treat the number as a click-to-call link. This is not always the case, so use HTML code to support this functionality. Seek specialist advice if you’re unsure of how to do this.

Using HTML for click-to-call

Use ‘tel:[telephone number]’ as the URL. Remove spaces between the numbers.

Remember that all webpages can be accessed internationally. Include the international dialling prefix if appropriate.

Don't use ‘phone words’

Always display the telephone number as digits. Don’t use ‘phone words’. Use the relevant 13 or 1300 number instead.

Some organisations use phone words to advertise their telephone number as a digit-word combination. Don’t do this, because some people find it hard to convert letters to numbers.