"For a simple return, for example, a single person filing a basic return," says Garwitz, "you just claim the credit right on the 1040." It's line 71 of Form 1040, line 42 of Form 1040A or line 9 of Form 1040EZ.

Claiming standard credit amounts
Most taxpayers also will find it's just as easy when it comes to the amount to enter on the appropriate lines of their tax returns.

The IRS has established standard credit amounts, calculated as average phone tax costs based on the total number of taxpayer exemptions.

More exemptions mean a larger credit

• One exemption is worth a $30 credit. • Two exemptions are worth $40. • Three exemptions will give you $50 back. • Four or more exemptions are worth a $60 credit.

"For 99 percent of taxpayers, that standard amount is the smartest thing to do," says Garwitz. "Tracking down records is, at a minimum, a pain in the neck and for a lot of us, it's impossible.

"But if you have significant phone charges, it might be worth it to file for your actual excise claim amount."

File new form for more
Of course, this means you must have your old phone records for the 2003 to 2006 eligibility period. You don't have to submit them to get the larger credit, but you will need that 41 months of information to complete Form 8913 and the work sheet found in the form's instructions.

For some people, the effort to track down records might be worthwhile. "If you had family out of state and you made significant long-distance calls to them during that time, you might have paid much more than the $60 maximum standard credit," says Garwitz.

In these cases, your number of exemptions doesn't matter. If you have the documentation, you can claim the exact amount you paid.

Be careful about getting that information, though. If you must contact your phone company for substantiation, make sure there is no charge or at least just a minimal one, or your credit could be spent on copies before you even file your return.

Special credit cases
While most taxpayers probably will claim the standard credit amounts on their 1040s, some will have to file for the exact amount of charges using Form 8913.

This is the case for dependents on someone else's tax return. The IRS says dependents cannot claim the standard amount. A typical instance would be a student at a distant university who frequently called home. The student can file for the phone tax credit if he or she paid the calling bill and taxes, but only by claiming the exact amounts paid.

Businesses also must file Form 8913 and claim either the precise amount of phone taxes the firm paid or use an optional formula created by the IRS that enables the companies to avoid going through 41 months of old bills.

The IRS also has created another phone tax form for individuals who don't have to file a return. These individuals can submit 1040EZ-T and have the credit amount refund directly deposited to a bank account. In this case, the taxpayer can only select one account, not the three-accounts deposit option available to filers of other 1040 versions.

Remember, too, that this is a one-time credit, available for only the 2006 tax year. You can, however, file an amended return within three years if you claim the standard amount on this year's return and subsequently determine that you would have received substantially more by detailing your exact phone excise tax payments.

And the credit applies only to long-distance taxes. Local and state telephone taxes are still being collected, and these amounts can't be counted toward the federal credit claim.

Freelance writer Kay Bell writes Bankrate's tax stories from her home in Austin, Texas, and blogs each day on tax topics at Don't Mess with Taxes.