Quick Answer: CenturyLink vs Xfinity
CenturyLink serves 4 million residential internet customers across 36 states with DSL (10-100 Mbps) and fiber through its Quantum Fiber brand (200-8000 Mbps). CenturyLink offers Price for Life rate protection, no data caps, and gigabit fiber starting at $65/month.
Xfinity is the largest cable provider in the US with 32 million customers across 40 states. Xfinity uses DOCSIS 3.1 cable technology to deliver 75-1200 Mbps with plans starting at $35/month, though data caps apply in most markets.
Quick verdict: CenturyLink Quantum Fiber wins if available (cheaper, faster, no caps). Xfinity wins if only CenturyLink DSL is your alternative.
Side-by-Side Comparison
This comparison differs greatly depending on whether CenturyLink fiber or DSL is available at your address. The table covers both scenarios.
| Feature | CenturyLink (DSL) | CenturyLink (Fiber) | Xfinity (Cable) |
|---|---|---|---|
| Speed Range | 10-100 Mbps | 200-8000 Mbps | 75-1200 Mbps |
| Upload Speed | 1-10 Mbps | 200-8000 Mbps | 10-35 Mbps |
| Price | $50/month | $65-165/month | $35-100/month |
| Data Caps | None | None | 1.2 TB (most markets) |
| Price for Life | Yes | Yes | No |
| Contracts | No | No | Optional |
| Equipment | Included | Included | $15/month rental |
| Latency | 30-80ms | 5-15ms | 10-25ms |
| Availability | 36 states (rural/suburban) | 50-60 markets (select neighborhoods) | 40 states (urban/suburban) |
Test Your CenturyLink Speed | Test Your Xfinity Speed
Speed Comparison
CenturyLink DSL vs Xfinity Cable
If CenturyLink only offers DSL at your address, Xfinity cable is significantly faster.
CenturyLink DSL:
- Advertised: up to 100 Mbps
- Typical speeds: 10-40 Mbps (depends on distance from central office)
- Upload: 1-10 Mbps
- Latency: 30-80ms
Xfinity Cable:
- Connect: 75 Mbps - $35/month
- Connect More: 200 Mbps - $50/month
- Fast: 400 Mbps - $65/month
- Superfast: 800 Mbps - $80/month
- Gigabit: 1000 Mbps - $90/month
- Gigabit Extra: 1200 Mbps - $100/month
Winner: Xfinity. Cable delivers 5-50x faster speeds than DSL.
CenturyLink Quantum Fiber vs Xfinity Cable
If CenturyLink fiber is available, the comparison reverses.
CenturyLink Quantum Fiber:
- 200 Mbps: $30/month (promotional)
- 940 Mbps: $65/month (symmetrical 940/940)
- 3 Gbps: $125/month (symmetrical 3000/3000)
- 8 Gbps: $165/month (symmetrical 8000/8000)
Xfinity Cable:
- Gigabit: 1000/35 Mbps - $90/month
- Gigabit Extra: 1200/35 Mbps - $100/month
Winner: CenturyLink Quantum Fiber. Symmetrical uploads (940 Mbps vs 35 Mbps), faster top speed (8 Gbps vs 1.2 Gbps), and cheaper pricing ($65 vs $90 for gigabit).
Run Speed Test Now to check your actual connection speed.
Coverage Comparison
Xfinity has broader urban coverage, while CenturyLink serves scattered rural and suburban markets.
CenturyLink Coverage:
- 36 states with residential internet service
- DSL footprint: 15-20 million homes (largest remaining DSL network)
- Fiber footprint: 2 million homes in 50-60 markets
- Fiber concentrated in: Seattle, Denver, Phoenix, Salt Lake City, Las Vegas, Portland
- Fiber availability varies by neighborhood even within cities
- Quantum Fiber expansion focused on existing profitable markets
Xfinity Coverage:
- 40 states with 110+ million households
- Strong urban and suburban presence
- Not available in: AK, AR, HI, ID, IA, KS, LA, MS, MT, NE, ND, OK, SD, WY
- DOCSIS 3.1 deployed across entire network
- DOCSIS 4.0 upgrades underway for multi-gig in select areas
Winner: Xfinity for total coverage. CenturyLink fiber is extremely limited geographically.
Important: Check which CenturyLink technology is available at your address before comparing. The difference between CenturyLink DSL and CenturyLink fiber is enormous. Enter your address at centurylink.com or quantumfiber.com to find out.
Pricing Comparison
CenturyLink fiber is cheaper than Xfinity at comparable speeds, but CenturyLink DSL delivers less speed for a similar price.
DSL vs Cable Pricing
| Speed | CenturyLink DSL | Xfinity Cable |
|---|---|---|
| 75-100 Mbps | $50/month | $35/month (Connect) |
| 200 Mbps | N/A | $50/month |
| 400 Mbps | N/A | $65/month |
CenturyLink DSL costs more per Mbps but includes Price for Life and unlimited data.
Fiber vs Cable Pricing
| Speed | CenturyLink Fiber | Xfinity Cable | Savings |
|---|---|---|---|
| 940 Mbps | $65/month | $90/month (Gigabit) | CenturyLink saves $25/month |
| Unlimited data | Included | +$30/month | CenturyLink saves $30/month |
| Equipment | Included | +$15/month | CenturyLink saves $15/month |
| Total gigabit cost | $65/month | $135/month | CenturyLink saves $70/month |
Annual Savings (Fiber vs Cable Gigabit)
- CenturyLink Fiber: $65 x 12 = $780/year
- Xfinity Gigabit (with unlimited + equipment): $135 x 12 = $1,620/year
- CenturyLink fiber saves $840/year
Price for Life Advantage
CenturyLink’s Price for Life guarantee locks your monthly rate permanently at your current address. Xfinity uses promotional pricing that increases by $20-40/month after 12 months. Over 3 years, this rate lock amplifies the savings.
Winner: CenturyLink Quantum Fiber for pricing. Xfinity only wins on pricing if CenturyLink offers DSL-only.
Pros and Cons
CenturyLink Advantages
- Price for Life guarantee locks rate permanently (DSL and fiber)
- No data caps on any plan (DSL or fiber)
- Quantum Fiber gigabit at $65/month (cheapest gigabit in most markets)
- Symmetrical upload speeds on fiber (940/940, 3000/3000, 8000/8000)
- 8 Gbps residential fiber available in select markets ($165/month)
- No contracts required on any plan
- Equipment included in monthly price
- No promotional pricing games
CenturyLink Disadvantages
- DSL speeds very slow (10-40 Mbps typical) in many areas
- Fiber availability extremely limited (2 million homes vs Xfinity’s 110 million)
- Poor customer service reputation with long hold times
- Confusing branding between CenturyLink and Quantum Fiber
- DSL upload speeds very slow (1-10 Mbps)
- Fiber installation takes 4-8 weeks
- Billing errors and autopay issues reported frequently
- No fiber expansion planned in many legacy DSL markets
Xfinity Advantages
- Faster than CenturyLink DSL (75-1200 Mbps vs 10-100 Mbps)
- Available in 40 states (110+ million households)
- Consistent cable speeds in most areas
- Multiple plan tiers for different budgets
- xFi app for network management and parental controls
- 21 million WiFi hotspots nationwide
- DOCSIS 4.0 upgrades coming for multi-gig speeds
Xfinity Disadvantages
- 1.2 TB data cap in most markets ($30/month for unlimited)
- Upload speeds limited to 10-35 Mbps on all cable plans
- $15/month equipment rental fee (or buy your own modem)
- Price increases after 12-month promotional period
- Evening congestion can reduce speeds 20-30% in dense areas
- No rate lock guarantee (prices rise annually)
- Professional installation fees ($75-100)
Which Should You Choose?
Your choice depends heavily on which CenturyLink technology is available at your address.
If CenturyLink Fiber Is Available
| Use Case | Recommendation | Why |
|---|---|---|
| Best Value | CenturyLink | $65 gigabit vs $135 Xfinity total |
| Fastest Speed | CenturyLink | 8 Gbps vs 1.2 Gbps |
| Upload Speeds | CenturyLink | 940+ Mbps vs 35 Mbps |
| No Data Caps | CenturyLink | Free unlimited vs $30/month add-on |
| Rate Stability | CenturyLink | Price for Life locks rate |
| Remote Work | CenturyLink | Symmetrical uploads for video calls |
| Content Creation | CenturyLink | 8 Gbps upload for video production |
| Gaming | Either | Both offer low latency on wired |
If Only CenturyLink DSL Is Available
| Use Case | Recommendation | Why |
|---|---|---|
| Speed Priority | Xfinity | 200-1200 Mbps vs 10-40 Mbps DSL |
| 4K Streaming | Xfinity | Reliable 25+ Mbps per stream |
| Gaming | Xfinity | Lower latency (10-25ms vs 30-80ms) |
| Multiple Devices | Xfinity | Cable handles 5-15 devices better |
| Budget with No Caps | CenturyLink | $50/month unlimited vs Xfinity caps |
| Rate Stability | CenturyLink | Price for Life at $50/month |
| Basic Browsing | CenturyLink | 10-40 Mbps adequate for light use |
How to Run a Fair Speed Test
To compare CenturyLink and Xfinity accurately, test under the same conditions.
Quick test steps:
- Pause large downloads, streaming, and cloud backups.
- Use Ethernet if possible. If not, test next to the router/modem.
- Run 3 tests during off-peak hours and 3 during peak hours.
- Compare download, upload, and latency together.
- Note the plan tier you are on for each provider.
CenturyLink DSL note: DSL speeds are limited by distance from the central office. Check your modem’s sync speed (admin page at 192.168.1.1) to understand your line’s maximum capability. Your speed test cannot exceed the sync speed regardless of plan tier.
CenturyLink Fiber note: Fiber delivers full advertised speeds consistently. A wired connection should show 890-940 Mbps on the gigabit plan.
Test Your CenturyLink Speed | Test Your Xfinity Speed
Frequently Asked Questions
Should I choose CenturyLink or Xfinity?
Check CenturyLink’s availability at your address first. If Quantum Fiber is available, choose CenturyLink fiber ($65/month gigabit, symmetrical uploads, no caps, Price for Life). If only CenturyLink DSL is available at 10-40 Mbps, choose Xfinity cable for faster speeds. The technology at your address determines the answer.
Is CenturyLink Quantum Fiber the same as CenturyLink?
Yes. Quantum Fiber is CenturyLink’s rebranded fiber service, both owned by Lumen Technologies. Fiber customers use quantumfiber.com. DSL customers use centurylink.com. The fiber infrastructure and billing system are the same company. Quantum Fiber offers speeds from 200 Mbps to 8 Gbps.
Does CenturyLink have data caps?
No. CenturyLink has no data caps on any residential plan, including DSL and fiber. Use unlimited data without overage fees or throttling. This is a significant advantage over Xfinity, which charges $10 per 50 GB overage beyond 1.2 TB or $30/month for unlimited data.
Why is my CenturyLink DSL so slow?
DSL speed depends on distance from the central office. Copper wire signal degrades over distance. Within 1000 feet of the office, you may get 80-100 Mbps. At 1-2 miles, expect 25-60 Mbps. Beyond 2 miles, speeds drop to 10-25 Mbps. Beyond 3 miles, sub-10 Mbps is common. CenturyLink cannot overcome copper physics.
Can I switch from Xfinity to CenturyLink fiber?
If Quantum Fiber is available at your address, switching saves $70/month compared to Xfinity Gigabit with unlimited data and equipment. Note that fiber installation takes 4-8 weeks. Maintain Xfinity service during installation to avoid downtime. Cancel Xfinity only after CenturyLink fiber is active and tested.
Summary
CenturyLink vs Xfinity is not a simple comparison. The answer depends entirely on which CenturyLink technology is available at your address.
If CenturyLink Quantum Fiber is available, it beats Xfinity in every category. Gigabit fiber at $65/month with symmetrical uploads, no data caps, and Price for Life undercuts Xfinity Gigabit at $135/month total cost. The 8 Gbps tier at $165/month is among the fastest and cheapest multi-gig options in the US.
If only CenturyLink DSL is available, Xfinity cable is the better choice for speed. DSL delivers 10-40 Mbps in most locations while Xfinity offers 200-1200 Mbps. CenturyLink DSL still wins on price stability ($50/month locked for life) and unlimited data, making it suitable for light-use households on a budget.
Test your actual speed: CenturyLink Speed Test | Xfinity Speed Test
Last Updated: February 12, 2026 Data Sources: CenturyLink official website, Quantum Fiber official website, Xfinity official website, Lumen Technologies investor relations, Comcast investor relations, FCC broadband data