How to Fix Slow Internet on Windows 11 – 10 Network Tweaks That Actually Work

I get this call from Toronto clients every week: “Mark, my internet is broken.” Nine times out of ten, the internet is fine – it is Windows 11 doing something weird. Here is the exact troubleshooting order I run, learned from a thousand support tickets.

How do I know if it is actually Windows or my ISP?

Run a speedtest at Speedtest.net first. Then test on a phone connected to the same WiFi. If the phone is fast and the PC is slow – it is Windows. If both are slow – call your ISP.

I have a 1 Gbps Rogers fibre line at home that should hit 940 down. When my Windows machine drops to 80 Mbps but my phone shows 920, the problem is not Rogers.

What are the 10 fixes in order?

1. Flush DNS. Open Command Prompt as admin. Run ipconfig /flushdns. Half of my “slow internet” tickets are stale DNS entries.
2. Switch to faster DNS. Default ISP DNS is usually the slowest. Settings, Network, Ethernet/WiFi, DNS server assignment, Manual. Set IPv4 to 1.1.1.1 (primary) and 1.0.0.1 (secondary) – Cloudflare. Or 8.8.8.8 and 8.8.4.4 (Google).
3. Update network adapter drivers. Device Manager, Network adapters, right-click your adapter, Update driver. Better: download the latest from Intel, Realtek, or your laptop OEM directly.
4. Reset TCP/IP stack. Command Prompt as admin: netsh int ip reset then netsh winsock reset. Reboot. Fixes a surprising number of weird issues.
5. Disable Large Send Offload. Device Manager, your network adapter, Properties, Advanced tab, find Large Send Offload v2 (IPv4/IPv6), set both to Disabled. Old chipsets handle this poorly.
6. Toggle IPv6. Some routers and ISPs mishandle IPv6. Network adapter, Properties, uncheck Internet Protocol Version 6 (TCP/IPv6). Test. If no change, turn it back on.
7. Check QoS Packet Scheduler. Same Properties dialog – ensure QoS Packet Scheduler is enabled. Counterintuitively, disabling it often hurts.
8. Look at Task Manager. Ctrl+Shift+Esc, Performance tab, Ethernet/WiFi. If something is hogging bandwidth (Windows Update, OneDrive sync, Steam), throttle it.
9. Scan for malware. Open Windows Security, Virus & threat protection, Quick scan. Then offline scan from the same panel. Botnet malware loves your upload bandwidth.
10. Reset network completely. Settings, Network, Advanced, Network reset. Nuclear option – removes all adapters and reinstalls. Reboot. Re-add WiFi passwords.

What about WiFi-specific slowness?

If you are on WiFi specifically, check the band. Windows 11 has a habit of preferring 2.4 GHz over 5 GHz for “range.” On most modern routers, you want 5 GHz or 6 GHz (WiFi 6E/7). In your router admin page, give the 5 GHz network a different SSID and connect to that one explicitly.

I cover full WiFi 7 setup in my WiFi 7 router guide.

Are there hidden Windows settings that throttle bandwidth?

Yes. Group Policy (gpedit.msc, Pro only) has a Reservable bandwidth limit under Computer Configuration, Administrative Templates, Network, QoS Packet Scheduler. Default is 20% reserved. Set to 0 to free it up.

Also check Windows Update Delivery Optimization (Settings, Windows Update, Advanced, Delivery Optimization). Disable downloads from other PCs unless you actually want LAN updates.

What if none of this fixes it?

If you have done all 10 and still slow, the hardware is suspect. Bad Ethernet cable (try Cat6, replace if older than 5 years), failing router, or a dying network card. Plug directly into the router with a new cable to isolate.

For broader Windows performance, my bloatware removal guide often frees up hidden bandwidth hogs. For browser-specific slowness, see my Chrome extensions roundup – some extensions absolutely tank your speeds.

Frequently Asked Questions

Will switching DNS really make websites load faster?

Yes, often noticeably. Cloudflare 1.1.1.1 has averaged 10-15ms response in Toronto vs 30-50ms on Rogers default DNS. That is faster page load every single time.

Should I disable IPv6 permanently?

No. Try it as a test only. Modern services depend on IPv6 – permanently disabling it can break things like Xbox Live and FaceTime.

Does Windows 11 24H2 throttle slow connections?

No specific throttle, but background services (Windows Update, Microsoft Store, OneDrive) are aggressive. Disable Delivery Optimization downloads from other PCs.

What is the fastest free DNS?

In North America, Cloudflare 1.1.1.1 and Google 8.8.8.8 trade blows. OpenDNS (208.67.222.222) and Quad9 (9.9.9.9) are runners-up. Test with the namebench tool.

Should I use a VPN to speed up my connection?

No – a VPN adds latency. The only exception is if your ISP throttles specific traffic (streaming, gaming). Then a VPN can route around the throttling.