What is throttling? - How and Why ISPs throttle your bandwidth

Internet Service Providers (ISPs) have the power to deliberately slow down your internet, and to make matters worse, many regularly do so. 

This practice is called 'throttling', and this guide will fill you in on everything you need to know about the frustrating practice.

What is throttling?

Throttling is a synonym for strangling and bottlenecking, but is often prefixed with the word 'bandwidth' in a computing context. 

Simply put, bandwidth throttling is when an internet service provider (ISP) intentionally slows down the speed of its service. It does this by restricting the speed at which a bandwidth intensive device like a server can actually receive the data it's supposed to be processing. 

Why do ISPs engage in bandwidth throttling?

Throttling is usually framed as a necessary, reactionary measure ISPs implement to manage network traffic and mitigate congestion across their network.

However, it is often implemented when an ISP cannot fulfill the internet speed-related promises it has made to its customers. Some providers simply cannot service thousands of people gaming in high definition. 

Internet usages that may lead to bandwidth throttling

• Playing high definition video games 
• P2P file-sharing/torrenting 
• Watching large quantities of videos 
• Above-average background internet usage 
• There are too many people on the same network

Throttling and government censorship

Throttling is a technique commonly used by authoritarian regimes to control their citizens' internet usage, especially in periods of political tension.

In their 2018 report, for example, digital rights group Access Now found at least 22 instances of government-induced bandwidth throttling and suggested there were probably many more. Whilst compiling their 2019 report, they found 14. 

Can I stop my ISP from throttling my bandwidth?

There are a couple of ways to avoid being bandwidth throttled. The most obvious one is to use a VPN. VPNs reroute all your internet traffic through a private server before it reaches the internet, masking your IP address. 

Although it's largely a myth that VPNs speed up your internet connection - after all, your data packets have to make a longer journey - if you're experiencing bandwidth throttling, it may be an occasion where the inverse is true.  

Importantly, throttling doesn't happen to everyone - ISPs can see what you're doing on the internet and can decide to throttle your bandwidth for a number of reasons. 

If you're looking for a VPN for ISP throttling, it might be worth checking out our fastest VPNs that are tested daily, or our top VPN picks to use whilst gaming. 

The only other real alternative is to change your ISP - not all ISPs take the same approach to bandwidth throttling, and you may find this to make a more significant difference for a negligible price difference.

Check out our how to bypass bandwidth throttling guide for some information about how you can bypass these issues.

Can ISPs block VPNs from doing this?

Although VPNs stop your ISP from seeing what you're doing when you're using a VPN, they don't necessarily prevent them from seeing you're using one. In theory, they could block all this traffic if they wanted to. But there are two reasons why this is a rarity:

• VPN usage is so widespread in 2024 that blocking all VPN connections would affect significant amounts of business and trade. 
• VPNs like ExpressVPN, NordVPN, and Surfshark offer obfuscation tools that disguise your VPN traffic as normal traffic. 

Are VPNs just anti-throttling tools?

Far from it. VPNs have a multitude of uses, and navigating around an ISP that is engaging in bandwidth throttling is just one of them. The best VPNs will also provide its customers with:

• A global network of servers to connect to 
• Access to geo-restricted content 
• Protection against malware and viruses 
• A more secure way to send messages and make payments
• An all-round enhanced level of privacy and a feeling of safety 

How to check if you're being throttled

Fast.com is a simple site devised by Netflix specifically for customers to test their connection speeds and work out if their ISP is throttling their bandwidth. All you need to do is know fast your internet package is supposed to be and you can compare it with the score you get on that website. 

You can also perform a speed test with a VPN to see if your ISP is restricting your speeds. Simply compare your connection speeds whilst it is active with your speeds when it is inactive. If your internet is significantly slower without a VPN, you have your answer. 

Throttling vs capping

A data cap is a limit on a pre-agreed data allowance between an ISP and a network user, and data capping occurs when the transfer capacity of data over a given medium is limited. 

This is different from bandwidth throttling, which we said above was related to restricting the speed at which a device receiving lots of data (such as a bandwidth-intensive server) receives it.   

Conclusion

If you think your ISP is throttling your bandwidth, take advantage of a provider's 30-day money-back guarantee so you can know for sure. 

If your connection is slower without a VPN, you're likely being throttled!