I say “hopefully” because DT doesn’t plan to plow that cash directly back into T-Mobile USA. Instead, DT said it would use that cash to retire debt, which would strengthen its financial position so it can fund future investments, including T-Mobile’s network upgrades.

These towers sit on some valuable cellular real estate: 83 percent are in the top 100 markets while 72 percent are in the top 50. But T-Mobile was more than ready to part with them as owning your own towers is quickly becoming an anachronism. There’s a lot of money to be made in leasing space on the same tower to multiple operators.

While it’s difficult for a T-Mobile to justify working with a direct competitor like Verizon or AT&T, cramming as many radios as possible onto a single tower mast is exactly what Crown Castle is in business for. After the deal closes Crown Castle will own or manage 30,000 towers in 50 U.S. cities.

The 7,200 towers represent only a fraction of T-Mobile’s 51,000 cell sites, the majority of which T-Mobile leases. The deal isn’t a straight up sale though. Crown Castle is buying exclusive rights to lease and operate the towers for about 28 years, after which it can purchase them outright. T-Mobile has also committed to remain a tenant at those cell sites for 10 years.

Image courtesy Flickr user radialmonster.

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