There are several techniques you can use to reduce the amount of data your VPN uses:
1Choose the right VPN protocol
VPN protocols are the set of instructions that govern how the VPN client (e.g. your smartphone) communicates with the VPN server.
There are a number of different VPN protocols to choose from, and some are more efficient than others when it comes to data usage.
Which VPN Protocol Uses the Most Data?
We tested five of the most popular protocols to calculate the size of their VPN/encryption overhead. Here’s what we found:
VPN Protocol |
Overhead |
Our Verdict |
Privacy & Security |
Speed |
WireGuard |
4.53% |
A new VPN protocol that is quickly establishing itself as the best on the market. It’s very quick and – as our results show – very efficient. If data usage is a concern and your VPN provider supports it, we fully recommend using WireGuard. |
High |
Very Fast |
IKEv2/IPSec |
7.88% |
A good protocol for mobile users because of its ability to cope with frequent network changes. There is speculation that IPsec has been compromised by the NSA however, so be careful using it for highly sensitive data. |
Medium |
Very Fast |
PPTP |
8.24% |
Might be sufficient to evade soft data caps, but PPTP has weak and outdated security. Avoid unless absolutely necessary. |
Low |
Very Fast |
OpenVPN UDP |
17.23% |
We recommend OpenVPN as the most secure VPN protocol on the market. The UDP version is faster than TCP, but offers a less stable connection. |
High |
Fast |
OpenVPN TCP |
19.96% |
We recommend OpenVPN as the most secure VPN protocol on the market. TCP is slower than UDP and will consume slightly more mobile data. |
High |
Moderate |
NOTE: We also tested the effect of different key lengths (128-bit, 192-bit, and 256-bit) and different ciphers (AES and Camellia) on data use. The results showed that these factors had very little impact on the protocol’s overhead, despite frequent misleading claims to the contrary.
Roughly speaking, the more data efficient a protocol is, the faster it will be. For instance, WireGuard, IKEv2/IPSec, and PPTP are some of the fastest VPN protocols around.
It is also commonly assumed that more secure protocols will have larger encryption overheads. While this is generally true, WireGuard is currently considered to be secure despite having the smallest overall overhead. Whereas PPTP has known security vulnerabilities but still increases data consumption more than IKEv2/IPSec, a comparatively safer protocol.
SUMMARY:
WireGuard is the most efficient VPN protocol when it comes to mobile data usage. In our tests, it increased data consumption by just 4.5%. By contrast, the industry-standard protocol, OpenVPN, uses the most data. It has an overhead of 17%-20%, depending on which transmission protocol you use.
2Turn off the VPN
It might seem obvious, but you can stop your VPN using data by simply switching it off.
We would usually recommend that you leave your VPN on all the time, because it’s an invaluable tool for fighting surveillance, protecting your privacy, and keeping you safe.
However, if you’re just using your VPN to occasionally unblock foreign Netflix libraries or protect your identity when torrenting, and data usage is an issue, it might make sense to turn it off when you aren’t engaged in those activities.
By only using the service when strictly necessary, you can avoid the VPN overhead and make your monthly data allowance last longer or avoid paying more in data roaming charges.
3Use Split Tunneling
In fact, some VPN services offer a specialized feature to help you do just that. VPN split tunneling lets you specify which apps and services you want to run through the VPN connection and which you don’t.
For example, you might choose to protect your sensitive web browsing and email activity with the VPN, but transmit high-bandwidth activity like streaming and gaming outside of the VPN in order to avoid the overhead.
Not every VPN offers split tunneling, though. We recommend using ExpressVPN or NordVPN if it’s something that appeals to you.

You can turn on split tunneling in the ExpressVPN app under Preferences > General.
4Enable compression
Compression is a method used by many VPNs to minimize the amount of data usage. It’s a bit like zipping a file before it goes over the internet and is especially effective for image file transfers.
Typically, your VPN will have compression enabled by default if it uses it. But it’s always worth taking a look in the Settings menu to double-check.

Its effectiveness depends on whether the images and other content were compressed in the first place.
Most internet-friendly file formats are compressed already, and uncompressed text is only a small part of the data we typically download.
That said, if extra compression is available, use it.