South African ISP & mobile network IP guide

Guides to the IP addresses used by South Africa’s main internet providers and mobile networks: the autonomous system numbers (ASNs) each one announces, whether you are likely to be behind CGNAT, and how to check your own IP.

Mobile networks

• Vodacom — Mobile network (also fibre and fixed-LTE); AS29975, AS36994, AS37114, AS37137
• MTN — Mobile network (also fixed-LTE, 5G and fibre); AS16637, AS12091
• Cell C — Mobile network; AS37168
• Rain — 4G/5G data-only network; AS37105, AS33762, AS37597, AS327840

Fibre ISPs and networks

• Telkom — Fixed-line, fibre and mobile operator; AS37457, AS37251
• Afrihost — Internet service provider (fibre, LTE, ADSL); AS37611
• Cool Ideas — Fibre internet service provider; AS37680
• Vumatel — Open-access fibre network operator (FNO); AS328829
• Openserve — Wholesale fibre and copper network (Telkom group)
• Webafrica — Internet service provider (fibre, LTE); AS328453

ISP vs fibre network: which one owns my IP?

South African fibre is mostly open access: a fibre network operator (FNO) such as Openserve, Vumatel, Frogfoot or MetroFibre lays the cable, and you buy internet from an ISP that rents it. Your public IP comes from the ISP, not the FNO. That’s why an Afrihost customer on Vumatel fibre sees “Afrihost” on FernTool.

Mobile data and CGNAT

Mobile networks share public IPv4 addresses among many subscribers using carrier-grade NAT, so port forwarding and inbound connections generally don’t work on mobile data, LTE or 5G home products. Fibre ISPs usually give each customer a public address. Read what CGNAT is and public vs private IPs.

Frequently asked questions

Which South African ISP am I using?

Open the FernTool homepage or this page. The network and ASN shown next to your IP identify the company that provides your internet connection.

Why does my IP show my ISP and not my fibre company?

Most South African fibre is open access. The fibre network operator provides the line, but the ISP you pay provides your IP address and routes your traffic.

Do South African mobile networks use CGNAT?

Yes. Mobile data on Vodacom, MTN, Cell C, Telkom and Rain is typically behind carrier-grade NAT, so many users share one public IPv4 address.

How do I get a static IP in South Africa?

Most fibre ISPs sell a static or fixed IP as an add-on. On mobile networks you usually need a business APN product.

ASNs and prefix counts from bgp.he.net and IPtoASN, checked 16 October 2026. Prefix counts change over time.