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Does Quantum Fiber (CenturyLink) give you a public IP? (CGNAT, static IP and IPv6)

Short answer: Yes, per customer reports: Quantum Fiber lines get a dynamic public IPv4, not CGNAT, including with the fiber box in transparent-bridge mode. New static IPs aren't available: CenturyLink says it no longer leases new static IP addresses (existing leases continue). IPv6 is partial: customers report only 6rd (IPv6 carried inside IPv4), not native IPv6. We haven't found an official statement on CGNAT, so that part is low confidence.

Does Quantum Fiber use CGNAT?

Customers (2024 to 2025) say no: fiber lines get a globally routable but dynamic IPv4, and that holds when the provider's fiber box is set to transparent-bridge mode (VLAN 201) so you can use your own router. We haven't found a statement from the company on it. The reports are cited on the Quantum Fiber / CenturyLink ISP page. Legacy CenturyLink DSL may differ; if you're on DSL, run the check below and tell us what you see.

Static IP on Quantum Fiber / CenturyLink

CenturyLink's static IP help page says: "We are no longer leasing new static IP addresses." Existing leases continue. So a new home customer can't get one, and a dynamic public IPv4 that changes from time to time is what you get. Compare other ISPs on static IP prices by US home ISP.

Terms, ports and IPv6

• IPv6: partial. Customers report no native IPv6, only 6rd (IPv6 carried inside IPv4; your router has to support it), and describe it as unreliable.
• Upload: symmetrical on fiber plans ("Equal Upload & Download Speeds" on its own site).
• Servers: not verified yet.
• Ports 25/80/443: not verified yet. If you've tested them, send a report.
• Brand change: the Quantum Fiber website footer now reads AT&T (checked October 2026). See the ISP changes log.

How to confirm on your line

1. Follow how to tell if you're behind CGNAT: compare the router's WAN IP with your public IP.
2. Run the checker. Its port test checks a forwarded port from outside, and the report sums up what you can host.

More detail and sources: Does Quantum Fiber / CenturyLink use CGNAT? · Can I self-host on Quantum Fiber? · Find ISPs by state and county

This site sticks to ISP facts. It doesn't review or recommend third-party products or services. Based on customer reports and the company's own pages; policies change.