As of this Sunday, new AT&T wireless customers will have but two options when it comes to text and picture messaging: either get an unlimited texting plan (for individual or families), or pay 20 cents (or more) for each and every message.

That’s bad news for those of us who don’t send and receive, say, 100 messages a day, and based on a quick survey of the post-paid messaging plans offered by the other big carriers, unlimited messaging plans are increasingly becoming the norm rather than the exception.

In other words, the days of getting monthly “buckets” of, say, 200 or 500 messages seem to be numbered.

The scoop on AT&T’s “streamlining” of its messaging plans comes from Engadget, which confirmed the news with AT&T and adds that the changes will take effect August 21.

AT&T also promises that current customers will get to keep their existing messaging plans (including the soon-to-be-extinct $10-a-month plan for 1,000 messages), even if they decide to change phones.

The other big carriers also seem eager to sign us all up for unlimited text/picture messaging plans, while at the same time weaning us off unlimited data for our smartphones.

So, what exactly are our messaging options for the big four U.S. carriers: AT&T, Sprint, T-Mobile, and Verizon Wireless?

I surfed around the various carrier sites and culled a few facts and figures, with the chart below taking AT&T’s upcoming plan changes.

First of all, check out the prices for paying per message. Twenty cents each, both to send and receive? Yikes—and that’s just for text messages, with AT&T charging as much as 30 cents per picture message.

Also, limited buckets of messages are becoming increasingly scarce. AT&T and T-Mobile don’t offer them at all, while Sprint and Verizon only offer a couple buckets each. (Verizon Wireless’s $20-a-month, 5,000-message bucket is intended for those on family plans, by the way, while individual lines can get unlimited messaging for the same price.)

The biggest bargain? T-Mobile’s $10-a-month unlimited messaging plan for individuals. Verizon Wireless, on the other hand, will only give you 500 messages for $10 a month.

While Sprint and T-Mobile will sell your separate individual and family messaging plans, they’re also seriously hyping their unlimited bundles (which include different combinations of voice, data, and messaging), with each carrier offering bundled unlimited plans starting at $49 a month.

Overall? Like it or not, the big carriers seem to be pushing us all toward unlimited messaging plans—and hey, that’s great for those who send thousands of SMS messages a month, but it’s not so wonderful for anyone (like me, frankly) who only needs to fire off a text or two a day.

So, what about you? Do you have an unlimited messaging plan or a bucket of messages—or do you pay per message?

(Photo credit: iStockPhoto)