T-Mobile uses mmWave—but it’s mostly on the sidelines

It’s pretty well-known that T-Mobile’s 2.5 GHz spectrum is its workhorse, on top of the 600 MHz that comprises the lowest layer of its spectrum “layer cake.” Its use of millimeter wave—which sits at the top of the cake—isn’t so well-known. But it’s there, most notably in private networks. T-Mobile’s mmWave deployment most recently was on display during last weekend’s Kentucky Derby, where NBC Sports used it to support eight iPhone 17 Pros to capture owner, trainer and jockeys’ family reactions in the stands. NBC also used T-Mobile’s 5G standalone technology for live broadcasts at the 2025 Ryder Cup and KPMG Women’s PGA Championship. T-Mobile’s 5G On Demand uses a technology called New Radio Dual Connectivity, or NR-DC, to connect its mmWave spectrum to mid-band spectrum, allowing for super-fast speeds at events like the Kentucky Derby. NR-DC is supported in the most recent iPhone software release; previously, it was in Android devices.