ISP Reliability Report 2026

Reliability rankings

What these metrics mean

• Uptime % — percentage of time the connection is active and passing traffic, measured from continuous monitoring across subscriber pools.
• Peak-Hour Drop — average speed reduction between 7–10 PM vs mid-morning baseline. A 10% drop is typical for cable; fiber usually shows under 4%.
• Avg Jitter (ms) — variation in latency across a 60-second test window. Jitter above 5 ms noticeably affects gaming and video calls. Values shown are median peak-hour readings.

Fiber vs cable reliability gap

The reliability gap between fiber and cable is most visible in the jitter column. Fiber ISPs consistently achieve under 2 ms jitter — cable ISPs average 3–10 ms, with spikes to 20+ ms during peak congestion. For gaming and video calls, this difference is more impactful than headline download speed.

Why T-Mobile and Starlink lag on reliability

5G fixed wireless reliability varies significantly by tower proximity, congestion, and weather. Starlink's LEO satellite network is improving rapidly but still shows higher jitter and more packet loss than wireline options. Both are best suited for areas without cable or fiber — not as upgrades from those technologies.

How to test your ISP's reliability

Run 3–5 speed tests at different times of day (morning, afternoon, peak evening). Compare the results — consistent numbers indicate a reliable line; large variance indicates congestion or hardware issues. Also check jitter on the SpeedTestHQ test, which reports it alongside ping.

Key findings

• Fiber ISPs are the most reliable by every metric: Google Fiber (98.5% uptime, 2.5% peak-hour drop, <1 ms jitter) and Verizon Fios (98.2% uptime, 3.0% peak-hour drop) lead all ISPs. Their dedicated fiber connections have no shared neighborhood segments, which eliminates the congestion-driven degradation that cable networks experience.
• Cable ISPs show meaningful peak-hour degradation: Spectrum drops 10% during 7–10 PM peak hours, Xfinity drops 9.5%, and Cox drops 8% — all significantly worse than fiber ISPs' 2.5–4% drop. This translates to real-world speed reductions of 50–100 Mbps on a gigabit cable plan during evening hours.
• Jitter is the hidden reliability gap between fiber and cable: Fiber ISPs consistently achieve under 2 ms jitter while cable ISPs average 3–8 ms, with spikes to 20+ ms during peak congestion. For gaming and video calls, 5+ ms jitter causes noticeable rubberbanding and call quality degradation even when average ping looks acceptable.
• Starlink and T-Mobile lag significantly on reliability: Starlink's 88.5% uptime and 25% peak-hour speed drop reflect the shared satellite bandwidth and weather sensitivity of LEO service. T-Mobile Home Internet's 91% uptime and 18% peak-hour drop reflect tower congestion variability. Both are best suited for areas without wired broadband options.

Methodology

Uptime percentages are estimated from continuous SpeedTestHQ monitoring across subscriber pools, cross-referenced with FCC outage reports and ISP status page histories over the 12-month period ending April 2026. Peak-hour drop represents the median speed reduction between 7–10 PM local time versus a mid-morning baseline, averaged across all qualifying wired Ethernet tests. Jitter values are median peak-hour readings from 60-second extended test sessions. ISPs require a minimum of 10,000 qualifying wired tests in the measurement period.

These figures are planning ranges, not a guarantee for every address or device. Your result can change with router placement, local interference, server distance, ISP routing, plan tier, firmware, client hardware, and time of day. For your own connection, run a wired speed test and compare it with Wi-Fi and peak-hour tests.

Frequently Asked Questions

Which ISP is the most reliable in the US?

Google Fiber leads on reliability with 98.5% uptime, just 2.5% peak-hour speed drop, and under 1 ms jitter. Verizon Fios (98.2% uptime, <1 ms jitter) and AT&T Fiber (97.8% uptime, <1 ms jitter) follow closely. All three are fiber ISPs — the dedicated fiber connection to each home eliminates the shared-segment congestion that causes cable reliability to degrade during peak hours.

How much does peak-hour congestion affect cable internet?

Cable ISPs experience meaningful degradation during the 7–10 PM peak window. Spectrum drops 10% on average, Xfinity 9.5%, and Cox 8% — compared to just 2.5–4% for fiber ISPs. On a 1 Gbps cable plan, a 10% peak-hour drop translates to losing 100 Mbps of throughput every evening. The cause is shared neighborhood segments in cable plant architecture, which fiber's point-to-point connections do not have.

What level of jitter is acceptable for video calls and gaming?

For video calls, jitter under 5 ms is acceptable — above that, participants may notice choppy audio or video freezes. For gaming, jitter under 3 ms is ideal; above 10 ms causes rubberbanding and hit-registration issues in competitive titles. Fiber ISPs deliver under 2 ms jitter consistently. Cable ISPs average 3–8 ms with spikes higher during congestion. Starlink's 10–30 ms jitter is the primary reason it performs poorly for competitive gaming despite its improved latency over GEO satellite.

Is Starlink reliable enough for primary home internet?

Starlink's 88.5% uptime and 25% peak-hour speed drop make it the least reliable option on this list — but context matters. For rural households where Starlink is the only broadband option, 88.5% uptime is far better than no service at all. For households with access to cable or fiber, Starlink is not competitive on reliability. Its performance is improving rapidly year-over-year as SpaceX expands satellite capacity and reduces per-subscriber congestion.