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Does Spectrum give you a public IP? (CGNAT, MAP-T and static IP)

Short answer: Mostly yes, per customer reports: most Spectrum home lines get a public IPv4 address. Some customers report MAP-T (shared IPv4 with a slice of the ports) or CGNAT in some markets, which breaks port forwarding. Static IPs are a Spectrum Business add-on; the residential policy says not to configure one.

Does Spectrum use CGNAT?

Generally not, but not everywhere. Customer reports say Spectrum mostly gives a normal public IPv4, while some lines are on MAP-T and some markets report CGNAT. Spectrum hasn't confirmed this on a page we found (medium confidence; an operator conference talk and customer threads are cited on the Spectrum ISP page). MAP-T isn't classic CGNAT, but at home the effect is similar: your IPv4 address is shared, so inbound port forwarding breaks. See no IPv4 on your line: DS-Lite, 464XLAT and MAP-T.

Path to a full public IPv4

If your line is shared: we haven't verified a Spectrum opt-out yet. Customers ask support to move the line off MAP-T or CGNAT; whether that works isn't confirmed. If you've done it, tell us how it went.

Static IP: Spectrum's residential internet use policy forbids configuring a static IP; static IPs are sold as a Spectrum Business add-on. We haven't found a published price yet; see static IP prices by ISP.

Ports and terms

• Ports 25, 80 and 443: none of them is on Spectrum's published blocked-ports list.
• Terms: the current residential policy (checked 2026-10-16) has no explicit "no servers" clause, but limits service to personal, residential, non-commercial use. Older versions banned servers not consistent with personal, residential use.

What about IPv6?

Customers report native IPv6 with a /56 prefix through DHCPv6 prefix delegation, not guaranteed to stay the same. MAP-T lines run IPv6 natively, so devices can be reachable over IPv6 if your router's firewall allows it. The checker shows whether IPv6 works on your line.

How to confirm on your line

1. Follow how to tell if you're behind CGNAT. On MAP-T, the router may show no normal IPv4 WAN address, or one that doesn't take inbound connections.
2. Forward a port and run the checker's port test. Its report sums up what you can host and the ways out.

More detail and sources: Does Spectrum use CGNAT? · Can I self-host on Spectrum?

This site sticks to ISP facts. It doesn't review or recommend third-party products or services. Based partly on customer reports; policies change.