Formatting phone numbers correctly

How to enter phone numbers in international format with a country code and avoid common formatting mistakes.

Last reviewed: 2026-07-22

Formatting phone numbers correctly

For Nexcal to call contacts reliably, phone numbers must be in an unambiguous format. Inconsistent or incomplete numbers are one of the most common causes of leads that cannot be called.

  • Use the international format with a country code, for example starting with a plus sign and the country dialing code.
  • Drop the leading zero of the national notation when you use the country code.
  • Avoid letters, brackets or explanatory notes in the number field.
  • Keep the format consistent across the whole file.

Common sources of error

  • a missing country code on numbers written in national notation only;
  • a duplicated country code, for example through an extra leading zero;
  • spaces, hyphens or slashes placed inconsistently;
  • cells formatted as numbers in the spreadsheet, which strip leading digits.

Hinweis: Format the phone column in your spreadsheet as text before saving. This keeps the country code and leading digits intact.

When a number is considered invalid

If Nexcal recognizes a number as invalid, the record is flagged during import or the lead cannot be called. In that case, check the notation and import the corrected number again. For more help, see invalid phone number.

Common questions

How do I write a national number correctly?

Use the country code and drop the leading zero of the national notation. A number written nationally with a leading zero thus becomes an unambiguous international number.

Are spaces or hyphens allowed?

Avoid inconsistent separators in the number field. A uniform notation reduces the risk of a number being classified as invalid.

Why does the country code disappear in my spreadsheet?

Spreadsheet programs often treat numbers as figures and strip leading digits. Format the phone column as text before saving.

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