T-Mobile customers in New York, Los Angeles, Dallas, Houston, Philadelphia, Atlanta, Miami, Washington D.C., and Detroit will be the first to notice the changes. T-Mobile has already been crowned the fastest 4G LTE carrier in the country. Part of the reason is the use of 10MHz + 10MHz 4G LTE service found in 43 metropolitan areas, which provides download speeds as fast as 72Mbps.
The carrier is also testing out wideband service with 15MHz + 15MHz and 20MHz + 20MHz configurations, which provides even faster speeds. In Dallas, where the latter configuration has been tested, download speeds as fast as 147Mbps were achieved. The carrier used spectrum it received from its purchase of MetroPCS to develop the wideband service.