Are you frustrated with your slow broadband? You are not alone. Most of us will experience a slowdown from time to time, and it is particularly grating if you rely on the internet for work or school. The good news is that a fair proportion of slow connections have a cause you can find and fix yourself, without paying anyone anything.
This guide covers the common causes first, then the practical fixes, and finally what to do if none of it helps.
Why is my broadband so slow?
There are many reasons your broadband could be slow. It could be your provider, your router, your device, or the wiring in your house. Identifying which of these is responsible is most of the work, because the fix for each is completely different.
Your broadband type sets the ceiling
Before troubleshooting anything, it helps to know what your connection is capable of. ADSL and fibre to the cabinet both use copper wire for the last stretch between the street cabinet and your house, and the further you are from that cabinet the more the signal degrades. No amount of tinkering inside the house will get you past that limit. Full fibre runs the whole way to the building and does not suffer from it. Our guide to how fibre optic broadband works explains why, and you can check what is available at your address to see which type you are on.
Megabits are not megabytes
A common source of disappointment is confusing megabytes (MB) with megabits (Mb). Most file sizes are shown in megabytes, so it seems reasonable to assume speeds are too, but they are not. There are eight bits in a byte, so an 8 Mb connection will at best transfer 1 MB per second. If your download manager seems to be reporting a figure eight times slower than you expected, this is usually why, and nothing is actually wrong.
Other devices and software
If you are using an older computer or device, it might not be able to keep up with a modern broadband connection, which can look like slow broadband when it is nothing of the sort. Multiple devices sharing one connection has a real effect too, since they are all drawing on the same bandwidth.
Large applications and updates can also hog your bandwidth. Try pausing any big downloads or updates until you have finished using the internet for the day.
Background uploads you have forgotten about
Cloud backup and sync tools such as OneDrive, Google Photos, iCloud and Dropbox carry on syncing in the background even when you are not using them, particularly after you have added a large batch of photos or documents. This competes for the same upload bandwidth you need for video calls and gaming, so it can cause noticeable slowdowns with no obvious cause. Check your sync apps for bandwidth throttling options, or pause them when you need the connection for something else. Our guide to broadband upload speeds explains why the upload figure matters more than most people expect.
Traffic management
Most providers use traffic management, sometimes called traffic shaping, to manage the data flowing over their network. They can give priority to certain types of traffic, such as video streaming or gaming, during busy periods. That keeps speeds high for popular activities but can make file downloads or browsing slower at the same times. Providers have to tell you about their traffic management policies before you sign a contract, so check their website or ask them.
Peak time congestion
One of the most common causes of slow broadband is simply everyone else being online. Demand peaks in the evening after work and school, and speeds drop for everyone on the same local network. If your connection is fine at 10am and poor at 8pm, congestion is the likely explanation rather than a fault.
Broadband line faults
A fault on the line is another frequent cause, and it can come from anything from bad weather to physical damage to the cable. If you suspect a fault, contact your provider, who can run tests remotely and send an engineer if needed.
Slow wifi
Very often the broadband is fine and the wifi is the problem. If speeds are poor in one room but acceptable next to the router, that is a wifi issue rather than a broadband one. Our guide to boosting your home wifi signal deals with this in detail.
Browser problems and malware
A slow browser can make the whole connection feel sluggish. Make sure you are on the latest version and clear the cache and cookies occasionally. Browser extensions are worth a look too, especially ones you have forgotten you installed, since many run constant background checks. Malware is the more serious version of the same problem, consuming bandwidth and resources in the background, so it is worth running a scan if things have deteriorated suddenly.
Bandwidth thieves
In densely built areas a single wireless signal reaches a lot of homes. If your router is unprotected or uses an outdated encryption standard, neighbours or passers by can piggyback on your connection. WEP encryption, once the default, has been thoroughly broken for years and can be cracked in minutes with freely available tools. Make sure your router is set to WPA2 at minimum, or WPA3 if your router and devices support it. Most routers supplied today default to one of these, but it is worth checking on anything that has been in place for several years.
Problems at the other end
Sometimes your broadband is fine and the site or service you are trying to reach is not. Before blaming your connection, check whether the service is down using a site such as DownDetector.
Practical ways to improve your broadband speed
1. Run a speed test first
Before changing anything, find out what you are actually getting. Run a broadband speed test at a few different times of day, and run it once with a device plugged straight into the router with an ethernet cable. That single comparison tells you more than anything else on this list: if the wired result is close to the speed you pay for, the problem is inside your home, and if it is well short, the problem is the line or the package.
2. Check how many devices are competing
If several people are streaming or gaming at once, the connection is being divided between them. Try reducing usage, or consider whether the package itself is now too small for the household. Our guide to what broadband speed you really need gives rough figures for different sized homes.
3. Move your router
Router position matters more than most people expect. Keep it in an open, central spot, up on a shelf or table rather than on the floor, and away from metal objects and thick walls. Test a few positions and compare speed test results rather than guessing.
4. Use a wired connection
Connecting directly to the router with an ethernet cable is the simplest way to get the best speed a connection can offer, and it removes wifi from the equation entirely. For anything stationary, such as a desktop, games console or smart TV, it is worth doing permanently.
5. Add a wifi extender or mesh system
If physical barriers stop the signal reaching where you need it, an extender or mesh system picks up the signal and rebroadcasts it further into the house. These make a real difference in larger or awkwardly shaped homes, though a wired connection will always beat them where it is practical.
6. Clear out startup and background apps
Programs that launch when you turn on your machine consume processing power and often check for updates constantly, using bandwidth as they go. On Windows 10 and 11, open Task Manager and look at the Startup Apps tab, or go to Settings, then Apps, then Startup. Disable anything you do not need running in the background.
7. Consider an iPlate on older connections
BT's iPlate removes the bell wire that made older telephones ring. That wire acts as a conductor for electrical interference from light fittings and household appliances, which can drag down broadband speed. It is a cheap device and can be worthwhile on ADSL or fibre to the cabinet services. It is only relevant if your connection still runs over a copper phone line. On full fibre there is no phone line or bell wire involved, so an iPlate does nothing.
8. Check your router or modem is not the bottleneck
An old router transmits a weaker signal and supports older, slower wifi standards. On cable connections, an ageing DOCSIS 3.0 modem can throttle your traffic, and these are being phased out in favour of DOCSIS 3.1. On full fibre the picture is different again, since your connection arrives through an ONT, or optical network terminal, rather than a modem, and any bottleneck is far more likely to be the router or the internal wiring. Before buying hardware, check it is approved for use with your specific provider.
9. Shorten the run to the faceplate
On copper connections, the greater the distance between your router and the broadband socket, the weaker the connection, largely because the supplied cables are of poor quality. Moving the router closer to the faceplate has been shown to improve speeds on ADSL lines. The quality of your ethernet cables is worth a thought too.
10. Keep your browser up to date
Most modern browsers update themselves, but not all do. Check you are on the latest version, usually under the About option in the browser menu.
11. Leave the router switched on
Broadband routers are designed to run continuously. Switching yours off at night can signal to the exchange that there may be a fault on the line, and it may respond by lowering your speed while it settles the connection again. Leave it on.
What if your speed still has not improved?
If none of the above helps, do not put up with it. Speak to your provider and ask them to explain why your speed is not meeting expectations.
If you are with BT, EE, Plusnet, Sky, TalkTalk, Utility Warehouse, Virgin Media or Zen Internet, they have signed up to Ofcom's Broadband Speeds Code of Practice. That gives you additional protection: if your provider cannot bring your speed up to the personalised minimum guarantee they gave you when you signed up, you have the right to exit the contract without penalty.
If the provider cannot resolve it and will not release you, you can escalate to an independent ombudsman once you have a deadlock letter or eight weeks have passed since you complained.
Switching to something faster
If your line is simply as good as it will get, the remaining option is a different connection. Switching is far easier than it once was. Under Ofcom's One Touch Switch process you only contact the provider you want to move to, and they arrange everything else, including telling your current supplier. You no longer need a code from your existing provider, and the move can often complete within a day.
Our page on switching broadband provider covers what to expect. To see what is worth moving to, compare broadband deals, look at full fibre packages if they have reached your street, or use the savings checker to compare against what you currently pay.