Verizon's iPhone debuted with an unlimited data plan, but Verizon has confirmed that it soon will transition to tiered data plans. Photo: Jon Snyder/Wired.com

Unlimited smartphone data plans are going the way of the dodo bird.

Verizon Wireless confirmed on Monday it would soon be changing its wireless data pricing plans in July, ending its longstanding unlimited data plan option for smartphone users, priced at a very affordable $30 monthly.

“We will move to a more usage-based model in July,” a Verizon Wireless spokeswoman told AllThingsDigital in an e-mail. “We’ll share more later.”

In other words, Verizon is moving to a tiered data pricing model, just like its rival AT&T did last year.

Although Verizon didn’t expound upon the exact details of the new pricing model, the mobile blog site Droid Life claims to have received inside information on the new tiered usage plan. Expected to debut on July 7, Droid Life claims the new model will cost $30 monthly for 2 GB, $50 monthly for 5 GB, and $80 monthly for 10 GB of data.

With the rise of smartphones over the past three years, mobile access to data connections has grown tremendously. U.S. smartphone data usage has spiked at an 89 percent increase from last year, according to research from Nielsen. Most users, however, are essentially paying the same amount for their data plans as they were a year ago. Effectively, this means a decrease in cost per megabyte of data — about half of what it once was.

And the carriers, of course, want to get paid more, so they’re altering their data plans to give customers less bang for their buck. AT&T ended its unlimited data buffet last year. In May, T-Mobile introduced a tiered pricing structure to high-speed data access that throttles your connection speed after reaching your allotted amount.Verizon pulled the data-throttling maneuver earlier in the year, although it tried to sweep it under the rug in an unpublicized memo. And now Verizon is getting ready to kill its unlimited data plan, too.

Sprint is currently the only carrier to offer an unlimited data plan. The company hiked its rates slightly at the beginning of this year, however, tacking on a $10 “Premium Data” plan fee for any customer who purchases a smartphone. The fee applies to both 3G and 4G Sprint phones purchased or upgraded during or after mid-January of 2011.

And then there’s tethering – the ability to share your smartphone’s 3G or 4G internet connection with another device, such as a computer. If you want to add tethering capability to your phone, prepare to shell out even more dough. AT&T charges you an extra $20 a month to enable tethering on your smartphone. Verizon may give you a better deal, although it’s still not cheap: According to Droid Life, an extra $20 a month to Verizon will get you tethering capability, as well as tack on an additional 2 GB of data to your monthly limit. Not a bad way to outdo AT&T.

Confused? Don’t worry, you’re supposed to be. Luckily, we’ve got an explainer chart below for some clarity on who’s offering what data plan, and for how much.

Update: Edited at 6:20 PST to reflect change to AT&T’s tethering rate policy.