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How to Fix Packet Loss
10 min read · Updated 2026-09-17
Packet loss means some data never arrives and has to be sent again. You see it as stutter in games, frozen video and dropped words in calls. Fixing it is a process of elimination: prove which segment drops the packets, then fix that segment rather than changing settings at random.
Key takeaways
- Any sustained loss above roughly 1 percent is noticeable in real-time applications; 0 percent is the target on a wired link.
- WiFi is the cause far more often than the provider — always retest over Ethernet before escalating.
- Loss that appears only under load is congestion, not a fault.
- Loss that appears at all hours on Ethernet usually means a cable, port or line fault.
- Collect timestamped measurements before contacting support; without evidence the call goes nowhere.
Step 1 — Confirm the loss is real and sustained
A single dropped request proves nothing. Run a repeated test over several minutes and record the percentage. Do it twice: once while the network is idle and once while someone streams or uploads. Note the time of day, because evening congestion behaves differently from a hardware fault.
Step 2 — Take WiFi out of the equation
Plug a computer into the router with an Ethernet cable and repeat the same test. If the loss disappears, the wireless segment is responsible and the rest of this list does not apply to your line at all.
- Move closer to the router and retest to gauge how much is signal strength.
- Switch to the 5 GHz band, which is far less congested than 2.4 GHz.
- Change channel away from your neighbours' networks.
- Remove interference sources: microwaves, baby monitors, older cordless phones, dense USB 3 hubs.
- Reduce the number of active devices, since airtime, not bandwidth, is the scarce resource.
Step 3 — Check the physical layer
On a wired link, packet loss is very often mechanical. Reseat both ends of every cable in the path, replace any cable that is kinked, crushed or older than the equipment, and confirm the port negotiated its expected speed rather than dropping to 100 Mbps.
For cable connections, loose or corroded coaxial connectors and unnecessary splitters are a classic cause. For DSL, check filters and the wiring between the socket and the modem.
Step 4 — Rule out congestion and saturation
A fully saturated uplink drops packets by design once the queue overflows. If loss only appears while a backup, game update or cloud sync runs, the fix is queue management rather than repair: enable QoS or SQM on the router, cap background uploads, and schedule large transfers outside the hours you need the connection.
Step 5 — Eliminate your own equipment and software
Restart the router and modem once, then leave them alone. Update router firmware and the network adapter driver. Disable a VPN temporarily, since a distant or overloaded VPN endpoint can add loss that has nothing to do with your line. Test a second device to be sure the problem is not one machine.
Step 6 — Escalate with evidence
If loss persists on Ethernet, at multiple times of day, with the VPN off and after a firmware update, the fault is almost certainly outside your home. Contact your provider with a timestamped record of measurements, the loss percentage, and the fact that you have already excluded WiFi. Ask specifically whether there is congestion or a known fault on your segment.
Put this into practice with a real measurement.
Run a packet loss test