Onslow: landline numbers and carriers
Onslow is one of the town-level numbering areas the ACMA register uses under area code 08 (SA, WA & NT). The register lists 35 number blocks for it with about 40,000 allocated numbers, held by 19 carriers. A landline that calls you from one of these blocks was issued for the Onslow area — though the line may since have been ported, and caller ID can be spoofed.
Source: ACMA register, data as of 31/08/2026
The carriers in Onslow
Onslow is spread across carriers: TELSTRA LIMITED leads with 25% of allocated numbers, and 19 carriers hold blocks in total. The register names the range holder; individual numbers may operate on another network after porting.
| Carrier | Blocks | Numbers | Share |
|---|---|---|---|
| TELSTRA LIMITED | 8 | 10,000 | 25% |
| SYMBIO NETWORKS PTY LTD | 6 | 6,000 | 15% |
| SOUL PATTINSON TELECOMMUNICATIONS PTY LIMITED | 2 | 4,000 | 10% |
| PRIMUS TELECOMMUNICATIONS PTY LIMITED | 3 | 3,000 | 7.5% |
| NETSIP PTY LTD | 2 | 2,000 | 5% |
| OPTUS MOBILE PTY LIMITED | 1 | 2,000 | 5% |
| ADARGA PTY LTD | 1 | 1,000 | 2.5% |
| C2A INTERNET.COM.AU PTY. LTD. | 1 | 1,000 | 2.5% |
| CHECK TECHNOLOGY GROUP PTY LTD | 1 | 1,000 | 2.5% |
| CHIME COMMUNICATIONS PTY LTD | 1 | 1,000 | 2.5% |
| GENNEXT ENTERPRISES PTY LTD | 1 | 1,000 | 2.5% |
| LMGPS LTD | 1 | 1,000 | 2.5% |
| NETERA PTY LTD | 1 | 1,000 | 2.5% |
| OPTUS NETWORKS PTY LIMITED | 1 | 1,000 | 2.5% |
| PIPE NETWORKS PTY LIMITED | 1 | 1,000 | 2.5% |
Number blocks registered for Onslow
The ACMA allocates geographic numbers in blocks tied to this numbering area. Every registered block for this area is allocated to a carrier.
| Block start | Numbers | Held by |
|---|---|---|
| 0851017000… | 1,000 | VIRTUTEL PTY LTD |
| 0851046000… | 1,000 | SOUL PATTINSON TELECOMMUNICATIONS PTY LIMITED |
| 0851075000… | 1,000 | NETSIP PTY LTD |
| 0851104000… | 1,000 | ADARGA PTY LTD |
| 0851133000… | 1,000 | THE TRUSTEE FOR READING FAMILY TRUST |
| 0851191000… | 1,000 | WHY PAY MORE 4 LESS PTY LTD |
| 0851214000… | 1,000 | NETSIP PTY LTD |
| 0851215000… | 1,000 | SYMBIO NETWORKS PTY LTD |
| 0851242000… | 1,000 | SYMBIO NETWORKS PTY LTD |
| 0851251000… | 1,000 | GENNEXT ENTERPRISES PTY LTD |
| 0851305000… | 1,000 | CHECK TECHNOLOGY GROUP PTY LTD |
| 0851336000… | 1,000 | C2A INTERNET.COM.AU PTY. LTD. |
| 0851365000… | 1,000 | LMGPS LTD |
| 0851395000… | 1,000 | PIVOTEL SATELLITE PTY LIMITED |
| 0851424000… | 1,000 | NETERA PTY LTD |
| 0851454000… | 1,000 | SYMBIO NETWORKS PTY LTD |
| 0891060000… | 3,000 | SOUL PATTINSON TELECOMMUNICATIONS PTY LIMITED |
| 0891112000… | 1,000 | PRIMUS TELECOMMUNICATIONS PTY LIMITED |
Excerpt: the 18 lowest of 35 allocated blocks (source: ACMA register).
Check a number from Onslow
Worth knowing
- Block data tells you where a line was issued, not who is calling — and scammers routinely spoof local landline numbers to make a call look nearby.
- Learn more: the Australian area codes guide and how caller ID spoofing works.