TCP vs UDP for VPN - Which Should You Use?
Use UDP by default - it's faster for streaming, gaming, and browsing. Switch to TCP for reliability or to get through firewalls (over port 443). Here's the full breakdown.
The Short Answer
Use UDP by default - it's faster and the right choice for streaming, gaming, calls, and everyday browsing. Switch to TCP only when your connection is unstable or a restrictive network blocks UDP: TCP is slower but more reliable, and over port 443 it disguises VPN traffic as ordinary HTTPS to slip through firewalls. Most VPN apps default to UDP, so you rarely need to change it unless you hit a problem.
TCP vs UDP at a Glance
| Factor | UDP | TCP |
|---|---|---|
| Speed | Faster | Slower |
| Reliability | Good | Higher (re-sends lost packets) |
| Latency | Lower | Higher |
| Firewall evasion (port 443) | Harder | Easier - looks like HTTPS |
| Best for | Streaming, gaming, calls | Unstable / restricted networks |
| Used by WireGuard | Yes | No |
| Used by OpenVPN | Yes | Yes |
When to Use UDP
UDP (User Datagram Protocol) sends data without waiting to confirm each packet arrived. That means less overhead, lower latency, and higher speed - which is exactly what you want for streaming, gaming, video calls, and general browsing. It's the default for good reason and the only transport WireGuard uses. For nearly everyone, nearly all the time, UDP is the right choice.
When to Use TCP
TCP (Transmission Control Protocol) confirms and re-sends any lost packets, making it more reliable on unstable connections - at the cost of speed. Its other strength is firewall evasion: run over port 443, TCP VPN traffic looks like normal HTTPS web traffic, so networks that block VPNs often can't detect it. Reach for TCP when UDP is blocked (some workplaces, schools, hotels, or censored regions) or when a flaky connection keeps dropping.
How to Switch
In an OpenVPN-capable app, the TCP/UDP choice is usually in the protocol or connection settings - switch to "OpenVPN (TCP)" when you need reliability or firewall evasion, and back to UDP for speed. If you're on WireGuard and hit a block, switch to OpenVPN over TCP as your fallback. If a VPN won't connect at all, changing transport is one of the first things to try - see our VPN not connecting guide. For the bigger protocol picture, read VPN protocols explained.