T-Fiber internet is slow

Loose cables or a router that needs a reboot

T-Mobile Fiber links slow speeds to loose or damaged cables and to a router that needs a restart. It asks you to measure the speed with the app's test first.

Is T-Fiber down right now? Operational: 7 problem reports in the last hour. If it were down for everyone, this problem could come from there; right now it looks normal.

Fix it

How to fix it

Check that the router has power and the cables are not loose or damaged.
Run a speed test in the T-Mobile Fiber app under My Network > Bandwidth Test.
If it is still slow, unplug the router for 30 seconds, plug it back in and test again.
Call T-Fiber support at 1-844-783-4237 if speeds stay low.

From T-Fiber's help pages: fiber.t-mobile.com, in our words. Checked on 5 November 2026. If the steps do not help, T-Fiber's own support is the next stop.

Internet not workingLoose cable, fiber line fault or router issue
Router light is redRouter can't get an internet connection
Can't sign inT-Mobile ID password or email conflict
Device won't connectDevice or router needs a restart

All common T-Fiber problems Live T-Fiber status

T-Fiber internet is slow

How to fix it

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