There is less cable access in NI compared to many places in the UK
Northern Ireland has the fastest average broadband speeds in the UK for people subscribing to 'up to' 8Mbps broadband packages, according to Ofcom.
The telecoms regulator found the average speed in NI was 4.1Mbps compared to a UK average of 3.9Mbps.
Ofcom said better average electrical line quality in NI than in the rest of the UK may be one factor.
However, it qualified its findings pointing to an error margin of up to 0.4Mbps in its research.
That means the average speed could be as low as 3.7Mbps or as high as 4.5Mbps
It also found that a lower proportion of homes in Northern Ireland have access to either cable broadband or local loop unbundled services.
This means that a larger proportion of Northern Ireland consumers are on 'up to' 8Mbps DSL services than in the rest of the UK.
Therefore, a larger proportion of those with high access line speeds are taking 'up to' 8Mbps packages than is the case in the other places in the UK thereby increasing average speeds for 'up to' 8Mbps subscribers.
Ofcom's Northern Ireland director Denis Wolinski, said: "It is very encouraging that some people here are enjoying the fastest broadband speeds in the UK, but we know that there are still parts of Northern Ireland, particularly rural areas, where speeds are much slower.
"Ofcom will continue to encourage the rollout of better, faster broadband services across the whole of Northern Ireland."
Overall the research found that broadband users are not getting the speeds they are paying for.
Nearly one fifth of UK broadband customers on an 8Mbps connection actually receive less than 2Mbps, it found.
The research showed that less than 9% of users received more than 6Mbps.
However, the report shows that average connection speed across the UK is 4.1Mbps, up from 3.6Mbps in January.
The UK government would like everyone in the country to have access to broadband speeds of 2Mbps by 2012.