Less than half of Manchester city centre is actually able to access EE's 4G network, it has been reported.
Tests executed in Manchester by data company RootMetrics revealed that only 40.2 per cent of the city centre could gain access to EE's high-speed service, according to the BBC.
Perhaps more worryingly, no 4G coverage could be found outside the city centre.
However, Bill Moore, chief executive of RootMetrics, has said that the results aren't quite as concerning as they initially appear. After all, 4G service in the US proved patchy upon its rollout, with 30 to 60 per cent coverage reported in some areas there.
The average 4G data speed stood at 17Mbps, over five times quicker than the 3G service offered by Vodafone, the area's next fastest mobile operator, with 3.1Mbps.
EE's average speed (from a combination of 3G and 4G) measured in at 7.6Mbps.
"Although EE's 4G service is much faster than any network currently available in the UK, our testing shows that 4G connections are not consistent even within a nominated area," stated Moore. "Customers need to be aware of this, as there will be an expectation of blistering fast mobile Internet speeds whenever they use their phones."
RootMetrics also revealed that 31 per cent of 4G tests achieved speeds higher than 10Mbps and 19 per cent failed to beat 1.5Mbps. It has in the past been recorded that speeds below 1.5Mbps are common for 46 per cent of 3G tests.
The tests were carried out during November, using off-the-shelf Samsung Galaxy S3s with LTE.
EE has just unveiled its 12 month SIM-only tariffs, which start at a monthly rate of £21 for 500MB of data.
Update: Since the publication of the tests, EE has said, "RootMetrics' reporting that 4G is only available in 40.2% of Manchester is wholly misleading. RootMetrics has measured an area they choose to name 'urbanised Manchester' that is considerably larger than Manchester city centre, which we have regarded as our 4G launch zone. In Manchester city itself ... we estimate our 4G coverage is currently in excess of 80% and increasing on a daily basis as we turn on more sites.
"The area covered by 'urbanised Manchester' in the RootMetrics report includes parts of Salford, Bury, Rochdale, Oldham, Tameside, Stockport and Trafford. Of those boroughs, only parts of Salford are due to be covered by 4G at this early stage of rollout, and we have delivered this coverage."
Further information can be found using EE's Coverage Checker.