Quantum Fiber

Quantum Fiber: a buyer’s guide

Quantum Fiber is a fiber-to-the-home brand that grew out of CenturyLink / Lumen’s consumer glass — and, as of early 2026, sits inside AT&T’s mass-market fiber purchase. On RSINC it appears in about 252 cities across 11 states, with Fiber as the primary technology on all 252 city listings. Sample directory communities include Tucson, AZ, Colorado Springs, CO, Golden, CO, and Apache Junction, AZ.

RSINC shows sample plan rows that include fiber delivered as pulses of infrared light through optical cables, with an advertised download example of up to 8 Gbps and an unlimited-data fiber row. Treat those as directory examples, not a promise that every listed city already sells an 8-gig tier at every address. City counts are relationships, not enabled-location totals. Compare Quantum Fiber with other options for your ZIP on RSINC, or call 1-877-697-2926.

History of Quantum Fiber — CenturyLink glass, Lumen brand, AT&T close

Quantum Fiber is a product brand, not a 19th-century telephone company with a new logo. The underlying plant comes from the CenturyLink wireline family: CenturyTel’s merger with Embarq (the former Sprint local-phone business) closed July 1, 2009, and the combined company adopted the CenturyLink name (legal name CenturyLink, Inc. in May 2010). CenturyLink later deployed true fiber-to-the-home in selected markets — public accounts often cite early gigabit FTTH in Omaha and then Las Vegas — as a different architecture from the company’s much larger copper FTTN / VDSL footprint.

The Quantum name arrived with a corporate split-branding. On September 14, 2020, CenturyLink announced it would operate as Lumen Technologies for enterprise and platform businesses (ticker change from CTL to LUMN on September 18, 2020). CenturyLink would remain the customer-facing brand for traditional copper-based residential and small-business services. In the same announcement, Lumen launched Quantum Fiber as a fully digital platform for fiber-based products to residents and small businesses, using Lumen’s fiber network. In other words: copper customers stayed on CenturyLink branding; lit FTTH was supposed to live under Quantum Fiber as that brand rolled out market by market.

Ownership of that consumer fiber book changed in 2025–2026. Lumen announced on May 21, 2025 that it would sell its mass-markets fiber-to-the-home business to AT&T. Lumen and AT&T both announced that the sale closed on February 2, 2026, for $5.75 billion cash. The deal covered substantially all of the related consumer fiber access network and customer relationships in eleven states, described as more than 1 million fiber customers and more than 4 million enabled fiber locations (AT&T’s close story highlighted new metro areas such as Denver, Seattle, and Salt Lake City). Lumen said it kept its national/metro fiber backbone, central offices, and copper-based consumer business; AT&T took the mass-market FTTH customers and access plant in those states.

Integration is not the same as an overnight rebadge. Reporting after close described AT&T standing up operations to convert former Lumen/CenturyLink fiber customers toward AT&T Fiber, while some bills and field ops still showed Quantum Fiber or CenturyLink during a transition period under two-year support agreements. AT&T has also discussed placing acquired network assets in a vehicle later referred to as Forged Fiber 37 with a possible wholesale/open-access path — a network-ownership detail, not a reason to assume your monthly brand, portal, or technician truck has already changed. For shoppers, the practical takeaway: RSINC still lists the Quantum Fiber slug; confirm whether your order, bill, and install team say Quantum Fiber, CenturyLink, or AT&T Fiber at the exact address.

What Quantum Fiber offers — FTTH where the drop is actually glass

Unlike mixed DSL/fiber incumbents, RSINC’s Quantum Fiber city labels are Fiber across the board. That still is not last-mile proof: a city relationship does not mean every subdivision is passed, and “up to 8 Gbps” is an advertised ceiling in the directory table, not the default residential tier. Where a Quantum (now AT&T-owned) fiber drop is live, expect symmetrical or near-symmetrical multi-hundred-megabit to multi-gigabit service, stronger uploads than cable or DSL, and latency friendlier for video calls and cloud work than satellite.

Do not mix this page up with remaining CenturyLink copper (DSL/VDSL) at the same street. Lumen retained copper consumer services; a neighbor on a copper pair is not on Quantum Fiber. Equipment, promotions, autopay rules, and whether a multi-gig SKU is sold on your block can change during the AT&T conversion. Confirm technology and provisioned speed before you order.

Who Quantum Fiber fits — and when to compare alternatives

Quantum Fiber fits households and small businesses in the 11-state directory footprint that can actually order fiber at the drop and want a fiber alternative to cable or 5G home internet. It is a stronger candidate in metros Lumen had already enabled — the kinds of markets AT&T cited when it closed the purchase — if your address is on the enabled list.

Compare alternatives when the address is still copper CenturyLink, when another fiber overbuilder (or AT&T Fiber from AT&T’s pre-existing plant) already serves the street, or when you need a single bill that definitely uses AT&T branding today. City-level Fiber labels on RSINC are not an install date. If you only need wireless mobility, shop AT&T wireless separately; this page is about the Quantum Fiber / acquired FTTH footprint.

Start with an address-level comparison on RSINC, or call 1-877-697-2926, before you treat any city-page label as an install date.

Quantum Fiber FAQs

Is Quantum Fiber still a Lumen brand?

Lumen sold substantially all of its mass-markets FTTH business, including Quantum Fiber, to AT&T; both companies announced the close on February 2, 2026. Some billing and field operations were described as remaining Quantum/CenturyLink during transition. Confirm the name on your order and bill.

Is Quantum Fiber the same as CenturyLink?

Related family, different last-mile story. CenturyLink remained the copper-era residential brand; Quantum Fiber was the 2020 fiber-facing brand. A CenturyLink DSL listing is not a Quantum Fiber drop.

Does “up to 8 Gbps” mean my house gets 8 gigabits?

No. That is a directory advertised maximum. Ask for the provisioned residential or business tier at your address.

How do I check Quantum Fiber at my address?

Call RSINC at 1-877-697-2926, or start from the RSINC homepage. Service options and installation eligibility vary by location.

Are published Quantum Fiber prices guaranteed current?

No. Verify current pricing, offers, fees, and terms before ordering. Call 1-877-697-2926.

Disclaimer

RSINC is an independent comparison site and is not Quantum Fiber, Lumen Technologies, CenturyLink, or AT&T. Directory city counts are relationships, not coverage percentages or subscriber counts. Speeds, prices, ownership details, and build maps change. All trademarks belong to their owners.