AT&T Buys Quantum Fiber: What Changes for Quantum & CenturyLink Customers

Updated on October 28, 2026

13 min read

Yes — Quantum Fiber is now AT&T. AT&T closed its $5.75 billion purchase of Lumen’s mass-market fiber business on February 2, 2026, and Quantum Fiber customers became AT&T Fiber customers. But the att quantum fiber merger only moved the fiber side of the house. If your service runs over an old copper DSL line, you did not move — you are still a Lumen customer, and that distinction decides everything else on this page.

Shopping rather than staying put? See current Quantum Fiber internet plans and prices, verified September 2026.

Is Quantum Fiber now AT&T?

Yes. AT&T announced the att quantum fiber merger in May 2025 and completed it on February 2, 2026. Lumen Technologies — the parent company behind both the Quantum Fiber and CenturyLink brands — sold its consumer fiber-to-the-home business outright. Quantum Fiber accounts, and CenturyLink accounts that were already served over fiber, now sit with AT&T.

The scale is what makes this one of the larger quiet consolidations of the year: roughly 1 million existing fiber subscribers plus about 4 million fiber-enabled locations, concentrated in Lumen’s western and midwestern territory — states including Washington, Oregon, Idaho, Utah, Colorado, Nebraska, and Iowa. AT&T placed the acquired assets into a subsidiary and has said it intends to sell a controlling interest to an equity partner, which is normal financial engineering and does not change who bills you.

Did my service actually move? Fiber vs copper

This is the single most misread part of the att quantum fiber merger. AT&T bought the consumer fiber business. It did not buy Lumen’s copper. Lumen explicitly retained its copper network, its Mass Markets copper-based customers, and its enterprise and wholesale fiber business.

So the practical test is simple: what does your service run on? If you were sold “Quantum Fiber,” or a CenturyLink plan delivered over fiber, you moved to AT&T. If you have a slower CenturyLink DSL plan over a copper phone line, you stayed with Lumen and nothing about your account changed. Not sure which you have? A quick speed test is a decent tell — DSL rarely clears 100 Mbps, and fiber is typically symmetrical, with upload speeds close to download.

What changes for Quantum Fiber customers?

Less than you would expect on day one, and more than you would expect over a couple of years. That is the standard shape of these transitions, and the att quantum fiber merger is no exception. It matched what we saw in the Frontier–Verizon merger earlier this year.

The honest caveat: “your plan carries over” is a statement about today, not a permanent guarantee. Acquired customers eventually get migrated onto the buyer’s billing platform and pricing book. That is when promotional rates, equipment fees, and renewal pricing tend to drift toward the new owner’s standard. It is the same pattern we flagged in our coverage of 2026 internet price increases — the announcement is quiet, the bill is not.

Should you stay, bundle, or shop around?

Because there is no early termination fee on either side, you have unusual freedom here. Three reasonable moves:

• Stay put if you have price-for-life. That is a genuinely good rate that AT&T is honoring. Do not trade it away for a 12-month promo that expires into something worse.
• Bundle if you were already an AT&T wireless customer — or were considering it. Roughly $20/mo off is real money, and it is the one clear consumer upside of the deal.
• Shop if your promo is expiring. Post-merger is exactly when retention offers are softest and competitors are most aggressive. Compare what else reaches your address before you auto-renew.

One more consideration specific to the att quantum fiber merger: AT&T is separately retiring its legacy copper phone network on its own footprint. If you also have an old landline, read our AT&T POTS line shutdown timeline — that is a different process, but it can land on the same household in the same year.

How long will the Quantum Fiber brand stick around?

Where it stands now: AT&T CEO John Stankey said on the company’s July 2026 earnings call that the conversion was “pretty much getting to the back end,” with accounts moving market by market. The deal brought about 1.1 million fiber subscribers and more than 4 million fiber locations across 11 states. Branding is still mixed: some former customers are billed as CenturyLink and others as Quantum Fiber, and AT&T hasn’t set a date to retire the Quantum name in favor of AT&T Fiber. (Fierce Network, July 28, 2026)

Brand retirements run on a slower clock than ownership changes. Ownership flipped on a single day in February; the signage, the app, the support numbers, and the email domains get replaced in phases over the following year or two. Quantum Fiber’s own customer notices have already begun steering people toward AT&T offers, which is the usual first visible step.

Expect the sequence to look roughly like this: billing platform migration first, then account portals and apps, then customer support routing, and finally the brand name itself. The useful thing to watch is not the logo — it is the billing migration, because that is the moment your plan gets re-papered under new terms. If you want a preview of how patient this process can be, the Charter–Cox transition is running the same playbook on a similar timeline.

None of that requires action from you. You do not need to re-sign anything, re-verify your identity, or accept a new agreement to keep service running after the att quantum fiber merger. If you receive a message demanding urgent account action because of the acquisition, treat it as a phishing attempt — merger transitions are a favorite pretext for scams, and legitimate carriers do not threaten disconnection over an ownership change.

What to do if you are shopping right now

If you are moving, your promo is ending, or you simply want to know whether you are overpaying, the att quantum fiber merger changes the math in two small ways. First, an address that previously showed “Quantum Fiber” now effectively shows AT&T Fiber, which may open bundle pricing that was not on the table before. Second, if you are a copper DSL household that did not move, you are now on a network its owner has openly deprioritized in favor of enterprise and wholesale — which is a reasonable prompt to look at what fiber or fixed wireless has reached your street since you last checked.

Start with the numbers: our Quantum Fiber plans and prices page shows the current $50 gig offer and the fees, checked against a live quote in September 2026.

Either way, the absence of early termination fees is the detail worth exploiting. You can compare, switch, and — if the new service disappoints — switch back, without a penalty hanging over the decision. That is rarer than it sounds in this category.

The broader lesson from the att quantum fiber merger is the same one every deal on this list teaches: the companies change, the wires mostly do not, and the only variable you control is whether you check your options before the renewal date rather than after it.