Head to head: Comparing AT&T, Sprint, T-Mobile & Verizon's 'unlimited' wireless plans for iPhone [u]

The first thing most users look at in a wireless data plan is the basic price of the plan. Sales or special promotions vary, and expire, so full prices of plans as offered on Feb. 27 without time-limited promotions are included here.

The first graph only includes plan costs, and doesn't include taxes, or pre-requisites for service.

The big differentiator between the two AT&T unlimited plans are speed — the less expensive Unlimited Choice has a maximum speed of 3 megabits per second, where the more expensive Unlimited Plus is limited only by network congestion.

Also, T-Mobile's plan encompasses all taxes and fees, where the others don't. This varies somewhat by location, but an assumption of an extra 10% because of the line-items may not be precise, but isn't absurd to assume for the others.

Video streaming

For AT&T subscribers after Feb. 27, video streaming resolution defaults to 480p with Unlimited Plus, but upgrading to 1080p is no additional charge — at least for now. Unlimited Choice users are limited to 480p, with no option for higher resolution as the 3 megabits per second hard speed cap won't support anything higher.

If you have any of the previously mandatory DirecTV services, they come "zero rated," so any video streamed from the service won't count against the soft cap. Additionally, users who bundle DirecTV Now with one of the new Unlimited plans get a $30 bill credit — but the discount can't be applied to early subscribers on the $35 per month "Go Big" tier.

After an update late on Feb. 16, Sprint has removed it's charge for HD streaming. Verizon and T-Mobile also include HD video streaming at no cost.

A variety of streaming services, including Apple Music, are zero-rated with Verizon and T-Mobile as well.

Caps? Not exactly unlimited, but close.

The numbers are similar across all four carriers: AT&T and Verizon limit full speed to the first 22 GB of data consumed, Sprint waits until 23GB, and T-Mobile's limit is 28GB. How much the 6GB swing between highest and lowest matters depends on the user.

We couldn't get representatives from any of the four to give us a firm rule on when the throttling takes place after the cap is exceeded. Generally, the limits appear to kick in during times with the most users are occupying a small area, using the most data.

Tethering

Sprint includes 10GB per month of mobile hotspot data per line, with Verizon and T-Mobile granting 10GB in total.

In an update on Feb. 27, AT&T is including 10GB of Mobile Hotspot data per month per line at full speed with Unlimited Plus. Data consumed after the 10GB is cut back to 128 kbit per second. Unlimited Choice users are not able to use tethering at all.

Device costs

At some point in a mobile device's lifespan from release to discontinuation, there are myriad promotions and sales. We feel that this is a dead heat between the big-four, regardless of when in the cycle you buy.

You've still got homework to do.

What numbers or graphs can't determine in this case is how well the assorted wireless networks perform in your particular area, and this alone may eclipse any other consideration. Overall performance is best determined by talking to colleagues, inspecting coverage maps, and getting a feel from (possibly apocryphal) accounts of the situation.

All of the major networks have done a lot of work in the last few years on coverage and speed, so older reports should be taken with a grain of salt.