On ‘Unlimited’ Phone Plans, the Limit Is Speed, Not Data

On a US phone plan, “unlimited” means you are not cut off and not charged for overage; it does not mean your speed stays the same however much you use. The carriers’ own terms add up to four separate limits: a priority allowance, sometimes a hard speed cut, a hotspot cap and a video resolution cap.

Verizon’s own definition is the narrow one: an unlimited plan lets you “use as much cellular data as you need without worrying about overage charges”. Speed is a separate promise, and each plan sets it in the fine print.

The four limits, plan by plan

Carrier · plan	Priority data	After that	Hotspot	Video
Verizon · Simplicity	Not stated	4 Mbps after 500GB a month	10GB, then 1 Mbps	720p
AT&T · Elite 2.0	Won’t slow based on usage	—	250GB, then 128 Kbps	4K UHD
AT&T · Premium 2.0	Won’t slow based on usage	—	100GB, then 128 Kbps	4K UHD
AT&T · Extra 2.0	100GB	May slow if the network is busy	50GB, then 128 Kbps	SD
AT&T · Value 2.0	5GB	May slow if the network is busy	3GB, then 128 Kbps	SD
T-Mobile · Experience Beyond 2.0	Unlimited	—	250GB, then 3G speeds	SD; up to 4K if activated
T-Mobile · Experience More 2.0	Unlimited	—	60GB, then 3G speeds	SD; up to 4K if activated
T-Mobile · Essentials 2.0	50GB	Further reduction	3G speeds	SD
Visible · Visible	Not stated	Slower than other traffic at busy times	Unlimited at up to 5 Mbps	480p
Visible · Visible+	Unlimited	—	Unlimited at up to 10 Mbps	1080p on 5G UW, 720p elsewhere

All figures are from each carrier’s own plan pages and terms, read 7 October 2026 and linked below. “Not stated” means the plan’s own description does not give one. Prices are left out on purpose.

Priority data and deprioritization

Premium data, or high-speed data in AT&T’s wording, is how much you can use each month before your traffic drops to the back of the queue on a busy tower. T-Mobile’s plans page gives the plainest definition: data “at the start of your bill cycle where you are prioritized higher than customers who are heavy data users”. Once it is used, “you are prioritized lower than other customers and you may notice lower speeds in times and places with network congestion.”

The condition is congestion. Verizon says deprioritized speeds return to normal “once the demand on the site lessens, or if you connect to a different site not experiencing high demand.” AT&T says the effect can “start and stop over a very short time period (often measured in fractions of a second)”. On an uncrowded tower, a deprioritized line can run at full speed; at a stadium event or at peak times, the examples AT&T gives, it is slower than the lines ahead of it.

T-Mobile’s Essentials 2.0 shows the allowance is not always top priority. Its plan card offers “50GB of premium data”, while the footnote says Essentials customers “may notice speeds lower than other customers and further reduction if using >50GB/month., due to data prioritization.”

AT&T says that for plans with a usage threshold it alerts customers when they reach 75% of it, though its network-practices page still gives retired plans as its examples.

Hard speed cuts are a different thing

A throttle is a fixed cap that applies whether or not the tower is busy. Verizon’s Simplicity plan, the one on its unlimited-plans page, cuts speeds to 4 Mbps after 500GB in a billing cycle for the rest of that cycle. Its plan description, unlike Verizon’s older Unlimited Welcome on the same page, does not mention congestion priority.

Verizon also has a network-wide rule for any mobile line: above the top 0.5% of users’ average (1.2 TB as of June 2026), it “may reduce data speeds to your device to 4 Mbps” for the rest of the month.

Hotspot has its own allowance

Using your phone as a hotspot draws from a separate, usually smaller bucket. After it runs out, AT&T slows hotspot to a maximum of 128 Kbps, Verizon Simplicity to 1 Mbps, and T-Mobile to “max 3G speeds”. T-Mobile markets Experience Beyond 2.0 as “Unlimited mobile hotspot included”; its terms make that 250GB of high-speed hotspot data, then unlimited at 3G speeds.

T-Mobile adds that on-phone data “is prioritized over tethering usage” and that for customers using more than 50GB a month, “primary data usage must be on smartphone or tablet”. Visible takes the other approach: no hotspot allowance, but a speed ceiling of 5 Mbps on its base plan.

All of these limits assume a signal. Where there is none, the question is satellite coverage, and what AT&T, T-Mobile and Verizon’s dead-zone venture has announced sets out what each carrier offers today.

Video resolution is capped separately

Carriers detect streaming video and hold it to a set speed. AT&T’s default is standard definition, which it describes as “480p/DVD quality” and limits to 2 Mbps on a 5G device and plan. T-Mobile streams video “at up to 2.5 Mbps (SD)” unless a plan that allows 4K has it switched on. Verizon’s network page says it aims for 480p or 720p to phones depending on the plan; Simplicity gets 720p, and a $10-a-month Premium Video Streaming add-on raises it to up to 4K.

This is one reason a speed test can look fine while video stays soft: the number a speed test measures is not the one a stream gets. AT&T notes that it may also count two tethered devices watching the same source as one video stream.

How to read a plan before you switch

The FCC requires a broadband label for each mobile plan, listing data allowances and linking to the carrier’s network-management practices. T-Mobile embeds them in its plans page. If you are weighing a carrier’s prepaid plan against its postpaid one, what prepaid gives up on the same carrier sets the terms side by side. For any plan, look for four numbers: priority data, what happens after it, the hotspot allowance and its fallback speed, and the video resolution.

If you do switch, the difference between an eSIM and a physical SIM covers the SIM side of the move.

Questions people ask

Is unlimited data really unlimited?

You are not cut off and not charged overage, which is what carriers mean by it. What can change is speed: after a set amount you may be slowed on a busy tower, some plans cut speed outright after a threshold, and hotspot and video have their own caps.

What is premium data on a phone plan?

The amount of data each month during which you keep normal priority on the network. T-Mobile defines it as data at the start of your bill cycle where you are prioritized above heavy users; after it, you may notice lower speeds where the network is congested.

What does deprioritization mean?

Your data waits behind other customers’ when a cell site is congested. Verizon and AT&T both say speeds return to normal when demand at the site eases or you move to a site that is not busy. On a quiet tower it has little or no effect.

Is deprioritization the same as throttling?

No. Deprioritization depends on congestion. A throttle is a fixed cap that applies regardless, such as Verizon Simplicity’s 4 Mbps after 500GB in a month, or AT&T’s 128 Kbps hotspot speed once the hotspot allowance is used.

Why is my hotspot slow on an unlimited plan?

Most plans give hotspot its own, smaller allowance. After it, AT&T slows hotspot to 128 Kbps, T-Mobile to 3G speeds and Verizon Simplicity to 1 Mbps. T-Mobile also prioritizes on-phone data over tethering.

Why does video look blurry on my unlimited plan?

Many plans cap video resolution. AT&T Extra 2.0 and Value 2.0 and T-Mobile Essentials stream in SD, which AT&T describes as 480p. T-Mobile’s Experience plans stay in SD until you activate 4K, and Verizon Simplicity streams at 720p.