T-Mobile US adds a $90 5 Gbps fiber tier with 10-year price promise

Rebecca Stone

T-Mobile US Inc. (TMUS) has launched its fastest fiber plan, a symmetrical 5 Gbps service marketed as “5 Gig,” at $90 a month with AutoPay and a 10-year price guarantee. The full fiber-optic connection offers equal upload and download speeds, putting the tier at five times the speed of T-Mobile’s 1 Gig plan.

T-Mobile US describes the service as “designed to handle online gaming, 4K streaming, video calls and multiple connected devices at the same time.” That language states intended use, not measured performance. The announcement provides no latency, uptime or busy-network throughput results, and no named executive or customer testimony validates the claim.

T-Mobile’s fiber lineup now comprises:

• Fiber 300 — $35 per month with AutoPay.
• Fiber 1 Gig — $55 per month with AutoPay.
• Fiber 2 Gig — $70 per month with AutoPay.
• Fiber 5 Gig — $90 per month with AutoPay.

The three lower prices exclude taxes and fees. Customers receive a Wi-Fi router, free professional installation, unlimited data, no annual contract and no monthly equipment fee.

Select plans also include unspecified promotional rewards and a mesh Wi-Fi extender for better in-home Wi-Fi coverage. T-Mobile presents the combination of higher speeds and stable pricing as a way to strengthen its US broadband position, meet rising household demand and attract customers into its fiber base.

What does the 10-year price promise protect?

T-Mobile says customers can keep their monthly internet price unchanged for the decade. That is a stronger commitment than a promotional launch rate, but the announcement does not spell out how taxes, fees, promotional credits or equipment charges behave over the full term.

The three lower prices explicitly exclude taxes and fees; the 5 Gig announcement does not repeat that qualifier. It also gives no calendar launch date, service map, homes-passed figure, subscriber count, churn rate or capital cost. Without those data, outsiders cannot judge how quickly T-Mobile can scale the offer or what it costs to add each customer.

How are AT&T and Verizon competing?

AT&T Inc. has joined Global Infrastructure Partners and CPP Investments to combine its fiber ventures and accelerate deployment across the United States. Its stated priorities are faster, more reliable connectivity, more broadband customers and integrated fiber and 5G services. The item gives no investment amount, build target or subscriber result for that partnership.

Verizon Communications Inc. is advancing fiber through network investment and strategic partnerships aimed at more homes and businesses. It signed a multibillion-dollar agreement with Corning Inc. covering more than 80 million miles of optical fiber for network expansion and AI infrastructure.

That 80 million-mile figure describes the scale of the Corning agreement, not installed fiber or planned residential coverage. Verizon provides no delivery schedule or allocation between broadband expansion and AI infrastructure, while its broader upgrade program targets network capacity and service reliability. The order signals investment ambition, not verified market reach.

Does T-Mobile have commercial proof yet?

T-Mobile expects the expanded lineup to support broadband growth, attract more customers and expand its fiber customer base. Those remain corporate aims: the announcement reports no new subscriber total, coverage expansion, revenue contribution or take-up rate.

A market snapshot places T-Mobile shares down 24.6% over the past year against an industry growth figure of 114%. The item does not define that industry comparison or connect it to the fiber launch, so investors should not treat the juxtaposition as operating evidence.

The commercial evidence remains limited: T-Mobile can state what the 5 Gig tier promises, but neither the price guarantee nor competitors’ infrastructure commitments establish where the service will run, how many households can obtain it or whether demand follows.

The next test is whether T-Mobile can turn the tier into paying households and disclose a US rollout timetable, while AT&T and Verizon convert their fiber partnerships and purchases into scheduled coverage.