Slow Internet Checklist: Step-by-Step Troubleshooting

Before calling your ISP, work through this list. Most "slow internet" complaints turn out to be a Wi-Fi problem, an old router, a background app, or peak-hour congestion — all things you can fix yourself without a technician. Each step takes less than five minutes. Start at the top and stop when you find the problem.

Step 1: Restart Your Router and Modem

This fixes more problems than anything else on this list. Unplug both devices from power. Wait 30 full seconds. Plug the modem back in first and wait 60 seconds for it to reconnect. Then plug the router in and wait another 60 seconds.

Here's why it works: routers build up junk over days and weeks. Their memory fills with stale data and incomplete connections that slowly drag performance down. A restart clears all of it. Routers also run 24/7 — unlike your phone or laptop, they never get a forced reboot. A power cycle fixes around 30% of home speed issues outright.

Step 2: Test on a Wired Connection

Plug an Ethernet cable directly from your router to your laptop and run a speed test. If the wired result is way faster than your Wi-Fi — say, 90 Mbps wired vs 35 Mbps wireless — you've found it. It's not your ISP. It's your Wi-Fi. Fix it with a better router position, the 5 GHz band, or a cable to devices that need fast, reliable speed.

If the wired speed is also slow, the problem is your ISP, your modem, or something that's degraded. Keep reading.

Step 3: Check the Time of Day

Run the same speed test at 7am and again at 8pm. If evening is a lot slower — say, 80 Mbps in the morning and 25 Mbps at 8pm — you're hitting ISP congestion. Cable internet is a shared connection. Between 7 and 10pm, everyone in your area is streaming, gaming, and downloading at the same time. The bandwidth gets split more ways and speeds drop.

This is very common and you can't fix it yourself. But it's worth documenting with timestamps if you want to complain to your ISP or switch providers. "My internet is slow" is easy to dismiss. "My speeds drop from 85 Mbps to 22 Mbps every evening between 7pm and 10pm, confirmed by tests on five straight days" is a lot harder to ignore.

Step 4: Check for Background Apps Eating Bandwidth

Apps downloading in the background are a surprisingly common cause of "slow internet" — when really the internet is just busy doing other things.

On Windows: Open Task Manager (Ctrl+Shift+Esc) → click "Performance" → click "Open Resource Monitor" at the bottom → go to the Network tab. Sort by "Total (B/sec)" to see what's using bandwidth right now.

On Mac: Open Activity Monitor (Spotlight → Activity Monitor) → click the Network tab → sort by "Bytes Sent/Sec" or "Bytes Recv/Sec".

Common culprits: OneDrive, iCloud Photos, Dropbox, Windows Update, Steam updating games, antivirus downloading definitions, and video playing in a background browser tab. Stop whatever's running before you test.

Step 5: Test a Different Device

If your laptop is slow but your phone is fast on the same Wi-Fi, the problem is your laptop — a network driver issue, a bad Wi-Fi adapter, or a wrong setting. If both are equally slow on Wi-Fi, the problem is the network. If both are slow even on Ethernet, the problem is your ISP or modem.

This step isolates the problem to device vs. network fast. Don't skip it — it saves you time.

Step 6: Check Your Router's Age and Position

A router more than 4 years old might not support your plan's speed. Older routers have slower chips and can only handle so much traffic per second. Even if your ISP is delivering full speed to the modem, the router becomes the bottleneck before the data reaches your device.

Position matters too. A router in a cupboard, behind a TV, on the floor, or in a corner loses 30–50% of its range compared to one that's raised up, central, and out in the open. Moving the router costs nothing and sometimes makes a big difference.

Step 7: Check the Cable Between Modem and Wall

A damaged coaxial or phone cable between the wall socket and your modem causes packet loss and speed drops that look exactly like ISP problems. Check the cable for kinks, sharp bends, visible damage, and loose connectors at both ends. A short replacement cable costs a few pounds or dollars and is worth trying. If the cable runs through a wall and you can't replace it, flag it to your ISP — fixing wiring inside the building is their job in most areas.

Step 8: Call Your ISP — With Evidence

Done all of the above and still slow on a wired connection at all hours? It's time to call. Have this ready before you pick up the phone:

• Your test results: exact speeds, times, and whether they were wired or Wi-Fi
• The pattern: always slow, only evenings, or only certain activities
• What you've already tried: router restart, cable check, device comparison
• How long the problem has been going on

ISPs respond much faster to specific data than vague complaints. "My internet is slow" gets you a script. "My wired download speed has been 18 Mbps instead of 100 Mbps for five days, confirmed across multiple tests at different times on two different devices" gets you an engineer visit.

Quick Reference Checklist