Unless you've always dreamed of quitting your day job and becoming a CPA, there's only one reason for you to do your own taxes: to save money.

The average tax-preparation fee for a federal return with itemized deductions and a state return is $205, the National Society of Accountants says. If you don't itemize, the average fee is $115.

But with tax software, you can prepare your own return for less than half that amount. Taxpayers with adjusted gross income of $54,000 or less can prepare and electronically file their federal returns for free via the IRS Free File program.

Desktop programs cost more than online programs, but they let you keep your financial information on your computer until you e-file your returns (or print them out and mail them in). If you're uncomfortable typing sensitive financial information into an online program, you may prefer a desktop program. The most popular desktop programs also let you prepare more than one return — a handy feature if you need to file returns for several family members.

For our annual tax software review, we tested desktop products from TurboTax and H&R Block, the leading makers of tax software. In past years, we've found pros and cons with both programs. But this year, there's a clear winner, despite its higher price. Here's what we found:

TURBOTAX DELUXE

TurboTax introduced a "Life Change" feature this year, designed to help users identify events in 2007 that could affect their tax bills. In addition to the obvious life-changing experiences, such as marriage, divorce or buying a home, the list includes tax-sensitive financial changes you might overlook, such as supporting a relative or sending a child to college. By clicking on the relevant changes, TurboTax spokeswoman Julie Miller says, you can tailor the interview process to match your tax situation.

Repeat users who import their 2006 return will appreciate a year-over-year comparison feature that TurboTax launched last year. If you paid taxes on interest, dividends or capital gains in 2006, the program shows the names of financial institutions and amounts reported on last year's return. This is a useful way to compare your taxable investment returns, deductions, real estate taxes and other items from year to year.

TurboTax also fared pretty well on the "oops" test, as in, "Oops, I forgot to add the $5.99 in interest I received from my credit union!" We were able to find the appropriate section from the interview, make the change and see how it affected our refund, in just a few minutes.

Price: The desktop version of TurboTax Deluxe Federal and State costs $44.95 for one federal and one state tax return. But if you want to e-file your returns, you'll pay an additional $17.95 for each return. The total cost, then, of preparing a federal and a state tax return and e-filing both returns is $80.85.

Taxpayers who are comfortable doing their taxes online can save money by using the online version of TurboTax Deluxe. The cost of preparing and e-filing a federal return is $29.95. A state return costs an additional $29.95 and includes e-filing, for a total cost of $59.90.

TurboTax also offers a free version of its online federal tax return for taxpayers who use 1040EZ or other simple returns. The program includes e-filing. You can find it at www.turbotax.com.

TAXCUT PREMIUM

H&R Block's TaxCut Premium is a competent software program, and it costs less than TurboTax. But this year, TurboTax's version was decidedly easier to use.

TaxCut offers only a "premium" version, so there is no decision on whether to buy the "basic" or the more expensive "deluxe."

But it also forces you to spend a lot of time answering questions about obscure tax issues. TurboTax does a better job of targeting the interview to your specific situation.

Our biggest quibble with TaxCut was its performance in the "oops" test. We found the process of changing an entry cumbersome. In one instance, we couldn't change it at all. But Derek Swords, director of product management, says TaxCut is designed to allow users to edit their entries and that customers can always use its search button to locate a particular section.

Price: The desktop version of TaxCut Premium costs $69.99, including a state return and e-filing for federal and state returns. The price also includes one "Ask a Tax Advisor" session, which ordinarily costs $19.95.

The online version of TaxCut Premium, including a state return and e-filing, is $44.95 and also includes one "Ask a Tax Advisor" session with a tax professional, either on the phone or by e-mail.

OTHER TAX PROGRAMS

Some free or low-cost tax prep programs: