How to complain about slow broadband speed

If you're not getting the broadband speed you were promised, follow these steps to complain to your provider and ask it to rectify the situation
Which?Editorial team

1. Check your broadband speed

Use a broadband speed checking service to see whether you are getting a significantly slower service than you should be.

If you are, your broadband provider may be in breach of contract. This will depend on the reason for the slow speed, and whether external factors are involved.

Unfortunately it can be difficult to quickly pin down the cause of the problem. Factors can include problems with your local exchange, the line into your house, or your router.

Key Information

Check your speed

Use the free Which? broadband speed checker tool to find out if your speed is up to scratch.

2. Check your broadband contract 

Check the small print of your contract. It may state that the advertised broadband speed is not guaranteed and is instead the maximum speed you can expect to get. 

The aftersale information you were sent should state a minimum guaranteed speed. Take a note of this number as it will be important moving forward.

Your contract may also warn of factors that could affect the speed you receive, such as the distance you are from the telephone exchange.

Your contract will likely explain that the provider can’t guarantee an uninterrupted service as the connection may be lost for a number of reasons beyond the provider's control.

However, you may still be able to claim against your provider if you were led to believe that you'd have the higher speed on a regular or permanent basis and that this promise induced you to enter into the contract.

3. Contact your provider

If your broadband is not achieving the speeds promised, the first step is to contact your provider. 

You can call or write to your provider and explain that you are not getting the speeds you were promised, or that the statements it made to you before you signed up were misrepresentations. 

Provide details of any information you were given about broadband speeds before you signed up, and try to provide a log of the issues detailing times and dates where you experienced slow service.

You should also ask your provider to check whether your access line speed (the download speed of your wired internet connection) is below your minimum guaranteed broadband speed.

Give the provider a couple of weeks to investigate your complaint and find a solution. Remember that it can be difficult to work out exactly why you're not getting the advertised service.   

Key Information

The Ofcom voluntary code

The Ofcom code is voluntary, but many of the biggest suppliers are signed up. You can find an up-to-date list of broadband providers who've signed up to the code on Ofcom's website.

These providers must give you the expected range of maximum speeds for your line at the point of sale. They must help you with your speed issues, and if your speed remains below your minimum guaranteed,  must let you exit your contract penalty-free. Alternatively, you can agree to continue the contract at a lower monthly cost. 

You can find your minimum guaranteed broadband speed in the information your provider sent you after the sale or upgrade.

If you want to change broadband supplier you only have to notify the company you wish to move to. Your new supplier will then handle every aspect of the change.

4. Make a broadband speed complaint

If you don't get a satisfactory solution from contacting your broadband provider, go through its formal complaints procedure. 

Keep records of all verbal or written communication as this can help your case should you need to take it further. 

Make a broadband speed complaint

If you prefer you can download this template letter to make a formal complaint to your broadband provider about the speed of your broadband instead. 

5. Try dispute resolution

All broadband providers must sign up to an alternative dispute resolution (ADR) scheme. Your provider will either be signed up to a scheme operated by CISAS or Ombudsman Services: Communications

If your broadband provider can’t or won’t help, after eight weeks you can take your complaint to the relevant ADR scheme. 

Both schemes have a form that you must complete to start the process. This will enable you to set out your issue and outline the remedy you're looking for.

If you're considering using the ombudsman, take a look at our step-by-step guide to complaining to an ombudsman