My Broadband is Slow

Slow broadband image

If you suffer from consistently slow broadband this section will offer you some hints and tips that should hopefully result in better broadband.

I thought my new broadband was meant to be faster?
Make sure its not your device or computer?
How do I know how slow my broadband is?
Why is my broadband slower than the connection speed the router shows?
Why are my speeds slow during the evening?
Will restarting my broadband modem fix my speeds?
Would buying new broadband hardware speed up my broadband?

So where's the problem?

The first step is you need to identify where the problem is, so let's walk through the possible causes:

  • Your device (computer, phone or tablet)—if your device is very old, has limited processing power or memory, or is full of five years of applications, it can be the case of your speed issue; you can usually confirm this by using another device and seeing if the speed is any better.
  • Your local Wi-Fi network—the connection between your device and the broadband router; this is only really likely to be an issue on wireless networks (although if you have 100Mbps Ethernet connections then you won't get the benefit of a 300Mbps+ broadband service on one device alone). Older routers may not support the fastest Wi-Fi services and some slow devices on your network may slow down the performance of your entire network. Check our Fix my Wi-Fi page for more details.
  • Your home telephone wiring—if your broadband service is provided over the phone line, your home telephone wiring could be causing problems; make sure you have micro-filters installed on every extension (unless your broadband does not require this; see our BT master socket page) and try moving your router to the master socket, disconnecting all extension wiring. The 'flat' extension wiring often sold by DIY stores can cause considerable interference issues.
  • The connection between your router and the exchange/cabinet—this is a common source of speed and service issues on phone line based broadband conenctions and there's often very little you can do about it. Talk to your broadband provider if you think this is causing an issue and they may be able to send an engineer to investigate (but be aware they may charge for this).
  • Congestion on the ISP broadband backhaul—this can be a common issue during 'peak times' such as evenings and weekends when broadband networks are most used; you can usually find if this is the cause using our Broadband Quality Monitor (BQM) tool as it demonstrates a recognisable pattern (BQM FAQ has details on how to identify this).
  • Traffic management in your ISP's network—There are various situations where providers route traffic in ways which can affect your speed including by prioritising some types of traffic against another.
  • Congestion on the wider Internet—this can happen on some routes and is especially likely during busy events. If you do a speed test on our site, this generally shouldn't apply for UK users, as we manage our speed test to ensure availability.

There are other possible causes of slow-downs, and most often you will find a speed issue is caused by many of these.

I thought my new broadband was meant to be faster?

If you have just switched provider or upgraded to a new package then obviously your hope is that you will be getting better speeds, but all too often adverts tend to over-promise.

The first step to knowing how fast to expect your broadband will be is to dig out the detail of what you ordered, so while you may have ordered an up to 76 Mbps connection not everyone will get that speed. Most broadband providers will give you a personal speed estimate when you order; this may be a single figure or a range and it is this estimate any faults or slowness need to be judged against rather than the 'up to' speed in any advert.

Make sure its not your device or computer?

Security updates and anti-virus scans will slow down your personal computer temporarily, so always double check that slow broadband is not just the result of a slow PC. Checking performance with a second device is always a good idea and while it seems obvious rebooting a computer rather than just putting it to sleep and waking it up can sometimes improve performance.

If you're using Wi-Fi (a wireless connection, which is almost certain if you're using a phone or tablet, often with laptops and even with some desktop machines), move your device to be closer to the broadband router or Wireless Access Point to see if that improves the speed. Better still, try connecting your computer to the broadband router using an Ethernet cable:

Ethernet Cable

Read our Wi-Fi troubleshooting page if your issue is down to wireless connectivity.

How do I know how slow my broadband is?

It is all to easy to get your bits and Bytes mixed up, or have a download running slowly so the best way to give your broadband connection a quick workout and get some meaningful figures back is to run a broadband speed test and make sure nothing else is using your connection.

Our speed test runs two download tests, the first the 'TBBx1' test is a single download designed to be representative of tasks such as video streaming, so if this is slow compared to the 'HTTPx6' test this will explain why video streaming is buffering a lot, on a good connection the two download tests should be almost identical. If using Wi-Fi try moving nearer to the router, or connecting a computer using an Ethernet cable to the broadband router.

Why is my broadband slower than the connection speed the router shows?

On ADSL2+ and VDSL2 (FTTC) services your broadband modem will connect at a speed dictated by the conditions at the time it synchronised with the hardware in the telephone exchange or cabinet. The figures shown by your broadband router in its web interface are the connection speed, but for getting data to and from the Internet there are what are known as protocol overheads i.e. the packets of data coming to you from a website are parcelled up into smaller changes that have extra bits of data for verification of the data and this means you normally only see 86 to 96% of the connection speed as the maximum result from a speed test or a file download. Full fibre (FTTP) services also have this issue, but since you have a fixed connection speed people notice this less often and sometimes services over provision to ensure speed tests can hit the sold speed.

Cable broadband services generally over provision by about 10%, so as long as the rest of your neighbours are not also downloading or uploading a lot you should be able to meet the speed you were sold.

Why are my speeds slow during the evening?

It may seem obvious but the peak time for broadband starts around 5pm during a weekday when school children are home and everyone is still at work, this ramps up until around midnight. This means that you can find that downloads that were very quick during the day slow down a lot at night. These slow downs are not normally down to a problem with broadband but are to do with the shared nature of the Internet, hence why business broadband is a lot more expensive because you are buying a dedicated amount of access to the Internet. Some providers endeavour to make sure the peak time is not much slower than off-peak, and thus it is possible to have a very different broadband experience between providers, so if your broadband feels slow, getting up early and testing at breakfast time is a good way of seeing if its the broadband or the provider. When broadband is slow due to the provider you will usually notice the lines from our speed tests are wandering around a lot.

Will restarting my broadband router fix my speeds?

In some cases yes, and given that routers are just small computers if it has not been restarted for a few months it may be the software just needs reloading and restarting by switching off and on will accomplish this.

Lightning even when a long way away can interfere with DSL signals, so if your broadband is slow in the time following a storm, it is worthwhile restarting the modem.

Caution: Do not switch off your router when you leave the house on a daily basis! With ADSL2+ and FTTC services switching the broadband router off and on a lot can make the remote broadband hardware think the line is unstable and a process called Dynamic Line Management (DLM) may kick in and slow the line down in response to try and make it more stable.

Top Tip: Check your microfilters on every single extension; another thing that catches people out, is that someone may move the phone to a different extension and if they forget to plug in a microfilter this will cripple the speeds for ADSL2+ and VDSL2, so always double check that everything is plugged in correctly, i.e. anything plugged into the phone line has a microfilter.

Would buying new broadband hardware speed up my broadband?

It depends. If your issue is about Wi-Fi speeds then the standards do keep improving so replacing a five year old Wi-Fi router could well improve speeds. You could instead consider adding some Wi-Fi extenders as well. Here are some dual-band extenders we would recommend:

If your issue is down to the broadband router/modem on the VDSL2 (FTTC) services, there are some reports that different hardware can make a 5-10 Mbps difference in connection speed (although it varies based on a number of factorrs). If you are considering buying new hardware for a VDSL2 service make sure that what you are buying supports Vectoring (noise cancellation) and G.INP (noise protection) - as a general rule VDSL2 modems based around a Broadcom chipset are the best performers. We are reluctant to make specific recommendations here as results can vary depending on the type of equipment you're connected to at the service provider end.

Broadband providers make a big song and dance about having the 'best' hardware citing comparisons or awards, but invariably better hardware is available but be wary of spending of hundreds of pounds on the latest all singing and dancing broadband router. Often the latest hardware releases don't have stable firmware, and you will find last years version at a much lower price point, stable firmware (software) and a lots of people already using it thus plenty of help out on various forums.