Southwark has the slowest broadband speed in London (10.4 megabits per second or mbps), according to research by consumers' association Which.
The other London boroughs with the worst broadband speed include Westminster (12.9mbps), Lambeth (13.2mbps) and City of London (13.4mbps).
Nationally, the Orkney Islands, Shetland Islands and Highland are the three Scottish local authority areas that have been ranked as the worst places in the UK for broadband speeds. Ryedale in Yorkshire and Purbeck in Dorset were also included in the bottom five, with the average recorded test in all those locations falling below 10mbps.
The fastest local authority areas for broadband speeds were Tamworth in the west Midlands, where the average speed is of 30.4mbps, followed by Reading and Adur in West Sussex.
Alex Neill, Which's managing director of home services, said: “Far too many households across the UK are suffering from slow broadband speeds, which can stop you being able to carry out essential daily tasks.
“We are encouraging everyone with broadband to use our speed checker so people can see if they are getting the speeds that they’ve been promised by their provider and find out how to complain if their speed is too slow.
“This will also help to further highlight where problem areas are across the UK, putting pressure on government and providers to help everyone get a good broadband connection.”
London boroughs - slowest speeds
|City of London||13.4|
|Slowest average broadband speed (Mbps)|
|Ryedale||Yorkshire and the Humber||9|
|Na h-Eileanan Siar||Scotland||9.1|
|West Devon||South West||9.5|
|Isle of Anglesey||Wales||10.1|
|West Somerset||South West||10.9|
|Kingston upon Hull, City of||Yorkshire and The Humber||10.9|
|Fastest average broadband speed (Mbps)|
|North East Lincolnshire||Yorkshire and The Humber||27.4|
|Nuneaton and Bedworth||West Midlands||26.1|
|Brighton and Hove||South East||25.3|
|Kingston upon Thames||London||25.1|