Where's Mine?

About 30 million stimulus payments totaling more than $27 billion were sent to taxpayers in the two weeks ending May 9, the U.S. Treasury Department said Friday.

The exact date you receive a stimulus check will depend on when you filed your tax return and on the last two digits of your Social Security number.

Taxpayers who opted for direct deposit, filed their 2007 return in time for the IRS to process it by April 15 and have a Social Security number ending with 00 through 75 are the likeliest to have received their payments this week or last. On jointly filed returns, the mailing schedule will be based on the first Social Security number listed.

Still, even if you met those criteria, there may be reasons why your payment is delayed. Also, it's not clear exactly how early taxpayers needed to file their tax return in order for the IRS to process it by April 15.

Mailing Schedule

This is the stimulus payment schedule for tax returns processed by April 15, the IRS said:

The IRS doesn't state how long it takes to process returns, but it can take two to three weeks. For stimulus payments to be part of the original delivery schedule, the IRS said tax returns must be "processed" by April 15 -- not "filed." That implies a later timetable applies to taxpayers who filed their return on or close to April 15, leaving little time for the return to be processed by that date.

For taxpayers who didn't choose direct deposit, stimulus payment checks will be mailed, and those checks will start going out May 9, the IRS said.

Exceptions Noted

There may be exceptions, the IRS warned. "A small percentage of tax returns will require additional time to process and to compute a stimulus payment amount. For these returns, stimulus payments may not be issued in accordance with the schedule, even if the tax return was processed by April 15," the IRS said in a press release in March.

"We have some returns that require a second look, that require us to pull them out of the processing for some reason or another," said Anthony Burke, an IRS spokesman, in a telephone interview. "It may not be that there's anything wrong with the return," he said.

The "vast majority of people" will receive their stimulus payment according to the posted schedule, Burke said, "but it's a big system, a lot of returns go through our pipeline" so some returns may not go exactly according to schedule.

If you expect a tax refund and chose to direct-deposit it into two or three separate accounts, the IRS will send your stimulus check in the mail. (To have your refund sent to more than one account requires you fill out Form 8888. See this IRS page for more information.)

If you owed taxes and sent a payment to the IRS with your return, you can still have your stimulus payment deposited directly into a bank or other account, the IRS said. Simply fill out the appropriate section on your return related to direct deposit, detailing your account information.

Some taxpayers may get a smaller stimulus payment than they expect, the IRS said. If you have a past-due federal or state income tax bill or some other type of past-due federal debt such as student loans or child support, your stimulus payment likely will be reduced by what you owe.

Also, the IRS said there's a new online calculator taxpayers can use to figure how much their stimulus payment will be. You'll need to have a completed 2007 tax return on hand to use the calculator.

Andrea Coombes is MarketWatch's assistant personal finance editor, based in San Francisco.