Does a VPN Slow Down 5G Mobile Data?

Yes, a VPN can slow down 5G mobile data. 

Sometimes the difference is tiny. Other times, you can watch a perfectly respectable 200Mbps 5G connection drop to something that suddenly feels far less exciting. 

That doesn’t necessarily mean the VPN is bad or your mobile network is struggling. A VPN simply gives your data more work to do. 

Without one, your phone sends traffic through the mobile network towards the website or app you want. 

With a VPN switched on, that traffic is encrypted, sent to a VPN server first, and only then forwarded to its destination. 

It’s a detour. 

And some detours are much longer than others. 

The VPN Server Was Practically on Holiday 

Marcus noticed his 5G connection felt sluggish one morning. 

YouTube took longer to start. Websites weren’t exactly crawling, but they had lost that instant snap he was used to. 

He ran a speed test with the VPN connected. 

Around 55Mbps. 

He switched it off. 

Nearly 190Mbps. 

The culprit became fairly obvious when he opened the VPN app. It was still connected to a US server he’d used the previous evening. 

Marcus was in Birmingham. 

His data had basically been taking a return trip across the Atlantic before loading ordinary websites. 

He switched to a UK server and most of the lost speed came back. 

Cloudflare describes this sort of unnecessary routing as the “trombone effect”, where VPN traffic travels a much longer physical route than it normally would. That extra distance increases latency. 

What Actually Slows the Connection? 

Several things can get involved. 

Possible cause	What you may notice
VPN server far away	Websites respond more slowly
Busy VPN server	Download speed drops
Encryption overhead	Small performance hit
Slower VPN protocol	Reduced throughput
Weak 5G signal	VPN slowdown feels worse
Nearby low-load server	Much smaller difference

The server location is usually the easiest thing to check. 

If you’re in London and only want basic privacy, there’s little point sending your traffic through California. 

Unless your data fancied the trip. 

Encryption Adds a Bit of Work 

A VPN encrypts traffic before it leaves your phone. 

That’s one of the reasons people use VPNs in the first place. 

Cloudflare notes that encryption and decryption can add latency because the device and VPN server have extra processing to do. 

On a modern smartphone, encryption alone usually isn’t enough to completely flatten a good 5G connection. 

Server distance and congestion often make a bigger difference. 

But when you’re starting with a very fast mobile connection, any bottleneck becomes easier to notice. 

A VPN server capable of handling 80Mbps will still give you roughly an 80Mbps ceiling even if your phone could otherwise pull 300Mbps. 

Your 5G hasn’t become slower. 

It has simply reached the slowest part of the route. 

Try a Server Closer to You 

This is the easiest fix. 

Most decent VPN apps let you choose individual countries or servers. 

Proton VPN currently recommends using a server closer to your physical location because longer distances increase latency. It also advises avoiding heavily loaded servers. 

So if your VPN feels rough: 

• Pick one showing a lower server load. 
• Connect to a nearby server. 
• Test again. 

Don’t compare London and New York and expect identical results. 

Physics remains annoyingly involved. 

The VPN Protocol Can Matter Too 

VPN apps often offer several connection protocols. 

You may see names such as: 

• WireGuard 
• OpenVPN 
• IKEv2 
• Automatic or Smart Protocol 

These aren’t just decorative settings. 

Different protocols can have different performance characteristics. 

Proton says WireGuard is generally its fastest protocol and notes that UDP-based connections are typically faster than TCP for WireGuard and OpenVPN in its service. 

You don’t need to spend Saturday night benchmarking VPN protocols. 

Leave the app on its automatic or recommended mode first. 

If performance is consistently poor, then try another option. 

Make Sure 5G Is Actually the Problem 

Mobile speeds naturally move around. 

Signal changes. 

Masts get busy. 

Your phone may switch bands. 

So test properly. 

Stand in the same place and turn Wi-Fi off. 

Run one speed test with the VPN disconnected. 

Then connect to a nearby VPN server and test again. 

If you get 200Mbps without the VPN and 170Mbps with it, that’s probably nothing worth losing sleep over. 

If you get 200Mbps and then 12Mbps, start checking the VPN server and settings. 

UK mobile networks are already shifting enormous amounts of traffic. Ofcom says consumers used more than 1.2 billion GB of mobile data per month in 2025, up 18% year on year, while 5G traffic itself grew 53%. 

The VPN isn’t the only thing that can make a connection slower at 6pm. 

Can a VPN Ever Make Things Faster? 

Oddly enough, yes. 

Cloudflare notes that a VPN can sometimes improve performance if a provider is intentionally throttling a particular type of traffic. Encryption can make that traffic harder to identify. 

That’s an exception, though. 

In normal use, expect either roughly similar performance or a modest drop. 

A VPN’s main job is privacy and secure routing. 

It isn’t meant to be nitrous oxide for your 5G connection. 

Where Talk Home Mobile Fits 

Talk Home Mobile currently provides 5G on compatible Android and iOS devices where 5G coverage is available. Its current service information also includes VoLTE and Wi-Fi Calling on supported devices. 

If Talk Home Mobile feels quick until your VPN connects, test the raw 5G connection first. 

If that works well, leave the SIM and APN alone. 

Try a closer VPN server, check server load and experiment with the VPN’s recommended protocol. 

If the connection is slow even with the VPN switched off, then signal strength, local congestion or coverage becomes a more sensible place to look. 

That order saves a lot of pointless tinkering. 

Final Thoughts 

A VPN can slow down 5G. 

But the size of the slowdown depends on where the VPN server is, how crowded it is, which protocol you’re using and how good the underlying 5G connection was to begin with. 

Start with a nearby server. 

Avoid overloaded locations. 

Compare speeds properly. 

And if your London phone is routing every Instagram Reel through Los Angeles, maybe give the mobile network a break. 

Your data is the one doing the long-distance travelling.