SpaceX says it has acquired the wireless spectrum needed to turn Starlink into a major mobile carrier, potentially challenging established cellphone providers. Shares in incumbent carriers fell as much as 8% following the announcement.

Elon Musk described the low-band spectrum acquisition as the final critical piece SpaceX needs to provide complete phone coverage across the United States. The company plans to use its Starlink satellites to deliver that service, extending its ambitions beyond satellite internet into the mobile phone market.

The acquisition brings SpaceX closer to nationwide mobile service, though the announcement provides no launch timeline, pricing, or information on compatible phones. The seller and purchase price have also not been disclosed. Still, SpaceX is presenting the deal as the foundation for a new national competitor. Existing carriers will now face competition from a satellite operator seeking a larger role in telecommunications.

Reliable cellphone coverage remains uneven, and adding another conventional carrier does little for places where building towers is difficult or uneconomic. However, a satellite-based competitor could target customers established networks have struggled to serve, making coverage a stronger selling point alongside price and data allowances.

Such a prospect also changes the competitive calculation for existing providers. Supposing that SpaceX can offer dependable service at an attractive price, carriers may be forced to work harder to retain subscribers rather than relying on the inconvenience of switching. The sharp decline in their shares reflects investors taking that possibility seriously, although it does not prove Starlink will deliver.

SpaceX could revolutionize the market by combining its satellite network with the newly acquired spectrum. A company that can expand without the need to build towers everywhere could force companies to reconsider where they invest and how they build their networks, with consequences for the deal well before Starlink begins offering the service.

Missed calls and delayed messages are a familiar part of traveling through areas with poor reception. Starlink’s planned service could make those trips easier by connecting an ordinary cellphone through satellites instead of relying entirely on nearby towers. SpaceX has not identified compatible phones or available features, leaving open whether customers would need new equipment and how much of their everyday phone use the service would support.

Musk’s promise of nationwide coverage leaves an important question for Americans who travel abroad or spend part of the year overseas. Replacing an existing carrier would also mean replacing its international roaming arrangements, details SpaceX has yet to provide. A phone that works on a remote American highway would not necessarily offer the same service after crossing into Canada or Mexico.

For retirees dividing their time between countries or families visiting relatives abroad, keeping another subscription could offset the savings from switching. Starlink’s domestic reach could be extensive, while frequent international travelers may still be better served by their current carrier’s arrangements.