Which is faster, CenturyLink or Xfinity?

CenturyLink delivers 20–940 Mbps and Xfinity delivers 50–1200 Mbps on wired tests. Which is faster depends on your specific plan tier and the technology available at your address — fiber to both houses will feel similar; fiber vs cable at the same plan tier favors fiber on upload and peak-hour consistency.

Is CenturyLink better than Xfinity for gaming?

For gaming, ping and jitter matter far more than headline download speed. CenturyLink on fiber will consistently beat Xfinity on cable or fixed-wireless; the reverse is also true. Check what technology each uses at your address, then aim for ping under 30 ms and jitter under 5 ms — both are measurable on a wired speed test.

Is CenturyLink or Xfinity cheaper?

Pricing moves constantly and varies by address, contract length, and promotional period. Check each provider's address-level availability tool on the day you sign up — use this page to compare performance, not current pricing.

Can I switch from CenturyLink to Xfinity easily?

Switching is usually straightforward: schedule Xfinity installation first, cancel CenturyLink only after the new line is running. Return any rented equipment to avoid charges. If you own your modem or router, check that it is compatible with the new ISP's technology before switching.

CenturyLink vs Xfinity: Speed, Plans & Verdict

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Comparing CenturyLink and Xfinity on real measured speed, upload symmetry, technology, and reliability. Updated 2026-04-27.

CenturyLink vs Xfinity: At-a-Glance

CenturyLink offers two very different products: legacy DSL (10–80 Mbps, slow) and Quantum Fiber (symmetric up to 940 Mbps, fast). This comparison focuses on Quantum Fiber vs Xfinity cable — if CenturyLink DSL is your only option, Xfinity cable wins on speed.

Metric	CenturyLink / Quantum Fiber	Xfinity	Winner
Technology	DSL or Fiber (Quantum Fiber)	Cable (DOCSIS 3.1)	Quantum Fiber
Download range	10–940 Mbps	75–1200 Mbps	Xfinity (top tier)
Upload speeds	10–940 Mbps (fiber symmetric)	5–35 Mbps	Quantum Fiber
Average ping (fiber)	~10 ms	~16 ms	CenturyLink Fiber
Peak-hour drop	<5% (fiber)	10–25%	CenturyLink Fiber
Data cap	None (fiber)	1.2 TB (most areas)	CenturyLink Fiber
Contract	None required	None required	Tie
US coverage	35+ states (DSL/fiber mix)	~75% of US households	Xfinity
Price range	$50–70/mo (fiber)	$20–90/mo	Xfinity (entry)
Upload symmetry	Symmetric (fiber only)	Asymmetric	CenturyLink Fiber

Plan Tier Comparison

CenturyLink Plan	Speed (Down/Up)	Xfinity Plan	Speed (Down/Up)
DSL (legacy)	10–80 / 1–10 Mbps	Connect	75 / 5 Mbps
Quantum Fiber 500	500 / 500 Mbps	Fast	500 / 20 Mbps
Quantum Fiber 940	940 / 940 Mbps	Gigabit	1200 / 35 Mbps

Quantum Fiber's upload on the 940 Mbps plan (940 Mbps) vs Xfinity Gigabit (35 Mbps) is a 27× difference. If you're on CenturyLink DSL, Xfinity cable is the faster option at every tier.

Real-World Use Case Comparison

Scenario	Quantum Fiber 940	Xfinity Gigabit
4K Netflix streaming	No issues	No issues
Upload 20 GB to cloud	~3 min at 940 Mbps	~75 min at 35 Mbps
Online gaming ping	~10 ms	~16 ms
8 PM peak hour	<5% speed drop	Drops 10–25%
Data cap risk	No cap	1.2 TB cap
Zoom video call quality	Excellent (symmetric)	Good (asymmetric upload)

When CenturyLink / Quantum Fiber Wins

Quantum Fiber is available at your address. Symmetric upload (940 Mbps up vs Xfinity's 35 Mbps), no data cap, and consistent peak-hour speeds make Quantum Fiber a clear upgrade over cable.
You work from home or upload frequently. The upload symmetry on Quantum Fiber is its biggest practical advantage — 940 Mbps upload vs 35 Mbps on Xfinity Gigabit is a 27× improvement.
You exceed 1.2 TB of data monthly. Quantum Fiber has no cap. Xfinity's 1.2 TB cap triggers overage fees or requires an unlimited add-on.

When Xfinity Wins

CenturyLink DSL is your only option from that provider. Legacy DSL (10–80 Mbps) is significantly slower than Xfinity cable at any tier. If Quantum Fiber hasn't reached your address, Xfinity is the faster choice.
You need a lower entry price. Xfinity's Connect plan starts at ~$20/mo for 75 Mbps. CenturyLink's fiber entry tier is ~$50/mo for 500 Mbps symmetric.
You need top download speed. Xfinity's Gigabit plan (1200 Mbps download) exceeds Quantum Fiber's top tier (940 Mbps) — though the upload difference is enormous in the other direction.

How to actually decide

Determine which CenturyLink product you'd get. Quantum Fiber and CenturyLink DSL are radically different. Check whether Quantum Fiber is available at your specific address — DSL availability doesn't mean fiber is available.
Compare upload requirements. If you video conference daily, stream to Twitch, or frequently back up large files to the cloud, Quantum Fiber's symmetric upload changes the comparison entirely.
Check the data cap impact. Xfinity's 1.2 TB cap affects heavy users. If your household uses more than 1 TB/month, factor in the potential overage costs when comparing prices.
Test after installation. Both providers offer cancellation windows. Run a wired Ethernet speed test immediately to confirm speeds match expectations before committing.

Verdict

If Quantum Fiber is available at your address, it wins over Xfinity cable — symmetric upload, no data cap, lower latency, and peak-hour consistency all favor fiber. If only CenturyLink DSL is available, choose Xfinity: cable is faster than legacy DSL at every plan tier. The decision hinges entirely on which CenturyLink product you can actually get.

Methodology

Speed ranges and latency figures are drawn from aggregated speed test measurements collected on SpeedTestHQ, supplemented by FCC Measuring Broadband America data and publicly disclosed ISP plan specifications. Peak-hour degradation estimates reflect the average difference between 7–11 PM and off-peak measurements across multiple metropolitan test nodes.

Plan availability, pricing, and speeds vary by address and change frequently. Verify current offers directly with each provider before signing up. This comparison reflects typical measured performance, not guaranteed speeds.

Frequently Asked Questions

Is CenturyLink the same as Quantum Fiber?

CenturyLink is rebranding its fiber internet service as Quantum Fiber. If you see "Quantum Fiber" at your address, it means fiber-to-the-home (FTTH) symmetric service — this is a completely different product from legacy CenturyLink DSL. DSL uses copper phone lines and caps out at 80 Mbps; Quantum Fiber uses fiber optic cable and delivers up to 940 Mbps symmetric.

Which is faster for gaming, CenturyLink Quantum Fiber or Xfinity?

Quantum Fiber delivers significantly better gaming performance — average ping of ~10 ms vs Xfinity cable's ~16 ms, and much lower jitter. The consistent, dedicated fiber connection means fewer lag spikes during peak hours. If gaming is a priority and Quantum Fiber is available, it's the better choice.

Does CenturyLink have a data cap?

Quantum Fiber (CenturyLink fiber) has no data cap. Legacy CenturyLink DSL plans vary by market — some have soft caps or speed reductions above a threshold. Xfinity enforces a 1.2 TB monthly cap in most areas. If you stream heavily, Quantum Fiber's uncapped service is an advantage.

Can I get Quantum Fiber instead of CenturyLink DSL?

Only if fiber has been deployed to your street. Check the Quantum Fiber address checker separately from CenturyLink's main site — fiber rollout is ongoing and not all addresses with DSL availability have fiber available. If Quantum Fiber isn't available yet, Xfinity cable is the faster interim option.

CenturyLink vs Xfinity: Which Is Better?