Numbers with prefix 21 in Australia
This page shows information about numbers beginning with 21 in Australia. If you received a call from an unknown number with this prefix, search the full number in our database to read community reports and comments. Landline New South Wales. Cost: Normal.
Search a number with prefix 21
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No numbers reported with prefix 21
We do not have public reports for this prefix yet. Try searching a full number or submit a report if you just received a suspicious call.
About numbers 21
Landline New South Wales. Cost: Normal. A prefix describes an allocation. Portability and caller-ID spoofing mean it cannot identify the caller on its own.
Source and review
Google libphonenumber (compiled from national numbering plans) · Document: 2026-08-28 · Reviewed: 2026-08-31
A prefix describes an allocation. Portability and caller-ID spoofing mean it cannot identify the caller on its own.