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🔢 Formatting numbers in your address book

ONSIM
Updated

If you receive a call from a saved contact but only see their phone number on the screen, it is almost always because the number is saved in a "local" format (starting with 0) rather than the "international" format (starting with +44).

The Correct Format (+44)

Numbers must be stored starting with the UK country code +44. When adding the country code, you must remove the leading zero from the area code or mobile number.

FormatExampleStatus
Standard UK0203 123 4567❌ Incorrect
Incorrect International+440203 123 4567❌ Incorrect
International Standard+44203 123 4567✅ Correct

Why formatting matters

  1. Caller ID Recognition: Your handset compares the incoming data to your contact list. If the incoming call is identified as +44... but your contact is saved as 0..., the phone often fails to "match" them, and the name won't appear.

  2. Call Connectivity: If you try to dial a number starting with 0044 or +440, our system may not recognize it.

  3. Tariff Errors: You might hear an automated message saying, "This call is not covered by your tariff plan." This happens because the handset is misinterpreting the extra zero and attempting to dial an invalid international destination.

Important: Disable "Dial Assist"

Modern smartphones have a feature called Dial Assist (iOS) or Assisted Dialing (Android). This feature automatically tries to "help" by adding country codes, which often conflicts with VoIP settings and leads to "Number Not Recognized" errors.

How to disable it on iPhone:

  1. Open Settings.

  2. Tap Phone (on newer iOS versions, this may be under Apps > Phone).

  3. Scroll to the very bottom and toggle Dial Assist to OFF.

How to disable it on Android:

  1. Open the Phone App.

  2. Tap the three dots (⋮) or Settings icon.

  3. Look for Assisted Dialing or Calling Accounts.

  4. Toggle Assisted Dialing to OFF.

Pro Tip: Bulk Editing

If you have hundreds of contacts stored with the leading 0, you don't have to edit them one by one.

  • App Solutions: Search your App Store for "Contact Fixer" or "Add Country Code." These apps can scan your entire address book and convert all numbers to the +44 format in seconds.

  • Manual Export: If you use Google or Outlook, you can export your contacts to a CSV file on a computer, use "Find and Replace" to change the leading 0 to +44, and then re-import them.

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