⚡ The short answer
- Yes — every VPN adds overhead. Encryption and routing take time.
- A fast VPN on WireGuard costs under 10% of your speed — imperceptible day-to-day.
- NordVPN (NordLynx) is fastest in our UK tests: 840 Mbps from 900 Mbps base.
- Older protocols like OpenVPN TCP can cut speeds by 40–60%. Protocol choice matters more than VPN brand.
- Connecting to a nearby UK server minimises latency and maximises throughput.
- For streaming, gaming, and video calls: any top-tier VPN on WireGuard is fast enough.
UK Speed Test Results (900 Mbps Fibre)
Tested via Speedtest.net CLI · London UK server · WireGuard / NordLynx / Lightway protocols · 40 runs per VPN · July 2026
No VPN — Baseline
Reference
NordVPN · NordLynx (WireGuard-based)
🏆 Fastest£2.99/mo
Surfshark · WireGuard
Best value£1.99/mo
ExpressVPN · Lightway (UDP)
£6.26/mo
Proton VPN · WireGuard
£3.99/mo
CyberGhost · WireGuard
£1.89/mo
Key takeaway: All five VPNs deliver 695+ Mbps on a 900 Mbps line. For context, 4K HDR streaming needs 25 Mbps. The slowest VPN here is still 27× faster than what Netflix 4K requires.
Protocol Makes More Difference Than Brand
The same VPN can behave very differently depending on which protocol you use. Here's how the major protocols compare on the same 900 Mbps UK fibre line with NordVPN:
| Protocol |
Speed (DL) |
Overhead |
Latency |
Security |
Best for |
| NordLynx (WireGuard) |
840 Mbps |
−7% |
+3ms |
Excellent |
Everything — default choice |
| WireGuard (Surfshark) |
810 Mbps |
−10% |
+5ms |
Excellent |
Everyday use, streaming, gaming |
| Lightway UDP (ExpressVPN) |
790 Mbps |
−12% |
+4ms |
Excellent |
Fast reconnections, mobile |
| IKEv2 |
620 Mbps |
−31% |
+12ms |
Good |
Mobile switching (WiFi ↔ 4G) |
| OpenVPN UDP |
530 Mbps |
−41% |
+18ms |
Good |
Older routers, compatibility |
| OpenVPN TCP |
380 Mbps |
−58% |
+32ms |
Good |
Bypassing firewalls (avoid otherwise) |
💡 Quick fix: If your VPN feels slow, open settings and switch to WireGuard or NordLynx. That single change is worth 200–400 Mbps on most connections.
Why Does a VPN Slow Your Internet Down?
Three technical factors cause the speed reduction:
1. Encryption overhead
A VPN encrypts every packet you send and receive. AES-256-GCM (used by most VPNs) is hardware-accelerated on modern CPUs, making this nearly free. But older VPNs using AES-256-CBC without hardware acceleration can burn significant CPU cycles — especially on mobile or older routers where processing power is limited.
2. Extra routing hop
Instead of connecting directly to a website, your traffic goes to the VPN server first and then onwards. That's an extra hop. Connecting to a London VPN server when you're in the UK adds perhaps 3–8ms. Connecting to a New York server adds 80–100ms. Always pick the nearest server for day-to-day use.
3. Server load and congestion
If a VPN server is overloaded — too many people connected — everyone slows down. Quality VPNs like NordVPN route you to the least-loaded server automatically. Cheaper VPNs with fewer servers often bottle-neck during peak hours (7–11pm UK time).
⚠️ Free VPN warning: Free VPNs routinely deliver under 10 Mbps due to overcrowded servers and intentional speed caps designed to push upgrades. They're fine for occasional light browsing but unsuitable for streaming, gaming, or anything that needs consistent speed.
Real-World Impact: Will You Actually Notice?
Even a 20–25% speed reduction is invisible in daily use for most people. Here's why, by use case:
📺
4K Streaming
Needs: ~25 Mbps
✅ No impact at all
🎮
Online Gaming
Needs: ~3 Mbps + low ping
✅ Fine on WireGuard (+3–8ms)
📹
Video Calls (HD)
Needs: ~3 Mbps up
✅ No impact
📁
Large Downloads
Needs: max speed
⚡ Slight slowdown on OpenVPN
🌐
Web Browsing
Needs: ~2 Mbps
✅ Unnoticeable
☁️
Cloud Backup
Needs: upload speed
⚡ Longer on slow upload plans
Bottom line: If you're on UK fibre (100 Mbps+), a top-tier VPN on WireGuard will never noticeably slow down streaming, gaming, browsing, or video calls. You'd only feel it on bulk transfers — and even then only if you're on OpenVPN.
5 Ways to Speed Up Your VPN Connection
- Switch to WireGuard or NordLynx: This alone can double your speed vs. OpenVPN. Every major VPN now supports WireGuard — look in Settings → Protocol → WireGuard.
- Connect to the nearest server: Use "Recommended" or "Quick Connect" to auto-pick the lowest-latency UK server. Avoid exotic locations (US, Asia) unless you specifically need them.
- Use a wired connection: Wi-Fi adds 5–30% overhead even without a VPN. Ethernet to your router eliminates wireless interference and gives the VPN a stable pipe to work with.
- Split tunnelling: Route only sensitive traffic through the VPN, letting streaming and other high-bandwidth apps use your direct connection. NordVPN and Surfshark both support this on Windows, macOS, and Android.
- Pick a VPN with 10 Gbps servers: NordVPN's UK servers run on 10 Gbps hardware. Cheaper VPNs often use 1 Gbps servers — a shared bottleneck when dozens of users connect simultaneously.
🕐 Peak hours note: VPN speeds can dip 10–20% between 7–10pm UK time due to server load. If your usage is flexible, morning or early afternoon gives the best sustained speeds.
Speed FAQ
Does a VPN slow down gaming?
Slightly — but on WireGuard the latency increase is just 3–8ms, which is imperceptible in gameplay. If your ISP throttles gaming traffic, a VPN can actually
reduce your ping by bypassing the throttle. See our
gaming VPN guide for detailed ping tests.
Does a VPN slow down streaming?
No — not with a modern VPN. Netflix 4K needs 25 Mbps. The slowest VPN in our test delivers 695 Mbps. Even if your ISP throttles streaming, a VPN bypasses that throttle, often making streaming faster.
Why is my VPN so slow?
The most common causes: (1) You're using OpenVPN TCP instead of WireGuard. (2) You're connected to a distant server. (3) Your VPN has overcrowded servers — common with free VPNs. Fix: switch protocol, change server, or upgrade to a faster VPN like NordVPN.
Does a VPN slow down your phone?
On modern smartphones (iPhone 12+, Pixel 6+), WireGuard runs almost entirely in hardware, so the overhead is negligible. Older phones on IKEv2 or OpenVPN may see a bigger dip, and battery usage increases slightly due to encryption processing.
Will a VPN slow down my upload speed?
Yes, similarly to download speed. In our tests, NordLynx dropped upload speed by 6% (110 → 103 Mbps). This only matters practically for people uploading large files frequently — video content creators, cloud backup users. For them, split tunnelling (routing only sensitive traffic via VPN) is the practical fix.
Can a VPN make your internet faster?
Yes — in one specific scenario. Some UK ISPs throttle certain types of traffic: gaming, streaming, or P2P. Because a VPN encrypts traffic, your ISP can't identify and throttle it. Users on ISPs that throttle Netflix or BBC iPlayer during peak hours often see better streaming performance with a VPN than without.