Quantum Fiber
Quantum Fiber, formerly Lumen and CenturyLink's fiber brand, is now owned by AT&T: 1 Gig for $50 with free installation and whole-home Wi-Fi 7 included.
Quantum Fiber plans at a glance
Our verdict
Quantum Fiber is now owned by AT&T, which bought Lumen's consumer fiber business. For now Quantum keeps its own site, plans and pricing, separate from AT&T Fiber.
New customers pay $50/mo for 1 Gig (from $80 standard, with $25 off plus $5 more for bank AutoPay), and 2 Gig or 3 Gig run $70 in select markets. 360 WiFi with Wi-Fi 7 is included, installation is free, and there's no contract. AT&T Wireless customers get $20/mo off their phone bill.
Two details to know before ordering: switching away from bank AutoPay, or two failed bank draws in a year, puts you back on the standard rate. And on some new installs, construction costs beyond the first $1,500 can be passed on to you; Quantum contacts you first.
Already have Quantum Fiber? Run our free speed test on a wired computer to see whether you get the speed you pay for, and see which speed test to use if results don't match.
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Jean founded ShopHighSpeed after trying to find one straight answer about business internet in his own town. He has been a Comcast and Verizon Fios customer, and ranks providers on what they actually deliver, not on what they advertise.
Frequently asked
Is Quantum Fiber owned by AT&T?
Yes. AT&T bought Lumen's consumer fiber business, and the brand is now "Quantum Fiber from AT&T". Quantum still sells its own plans for now.
Is Quantum Fiber the same as CenturyLink?
Quantum Fiber was CenturyLink's (Lumen's) fiber brand. CenturyLink's fiber areas are now Quantum Fiber from AT&T, while many of its copper areas went to Brightspeed.
How much does Quantum Fiber cost?
1 Gig is $50/mo for new customers with bank AutoPay ($80 standard). 2 Gig and 3 Gig are $70 in select markets. Paperless billing is required.
Does Quantum Fiber have data caps?
No. Quantum Fiber includes unlimited data with no overage charges.
How fast is Quantum Fiber?
Plans include 500 Mbps, 1 Gig and 2 Gig, with up to 8 Gig in select areas. All are symmetrical except 2 Gig.
Is it fiber or DSL at my address?
Quantum Fiber is fiber, though in limited cases the final connection from the curb uses a non-fiber line. CenturyLink DSL is a separate, slower product; check which one your address gets.
About Quantum Fiber
Quantum Fiber was the fiber brand of Lumen, CenturyLink's parent company. AT&T bought it on Feb 2, 2026, and Quantum customers in 11 states became AT&T Fiber customers. See our AT&T Fiber review for current plans.
More guides on Quantum Fiber
Sources
- Plan pages and Broadband Facts labels from AT&T Fiber, Frontier Fiber, gFiber (formerly Google Fiber), Quantum Fiber, checked Oct 2026
- Company press releases and regulatory filings on the ownership changes mentioned
Prices and offers change often; confirm at your address before you order. How we research
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