1. You're not afraid of numbers. Obvious, but important. I'm not just thinking about adding and multiplying here (and I know that computers can crunch numbers just fine). I'm also thinking about the basic issue of entering or writing down the numbers properly. Transposing two digits from a wage statement can result in more hassles for an innocent mistake than you would think possible.

2. You've got a simple return. Now, when I say a "simple" return, I don't mean it has to be a Form 1040-EZ. I'd like to think that most people who have little more going on in their financial tax lives than having a full-time job, owning a home with a mortgage, contributing to a fully deductible retirement account and making contributions to charities can do their own returns."If you're good at simple math, and the most complicated calculation you'll have to do is figure out the taxable portion of your Social Security, you may be a good candidate for doing your own returns," says Gretchen Beck, an enrolled agent in San Francisco.

3. You understand your own returns. I know, I know: You can use a computer program, so you say it doesn't matter if you understand your returns.Well, I disagree. You can certainly produce a very good return using a computer program, but it's still GIGO (garbage in, garbage out). If you enter something incorrectly, or don't understand the question being asked, you're not going to have as accurate a return as you could.That leads to the next point.

4. You're good at double-checking. The more information you have to enter on your return, the more possibilities for forgetting something or entering it in the wrong place or entering the wrong numbers. So having the patience to double-check your own work matters.Leon Taylor, a CPA in Portland, Ore., recalls having to amend several years' worth of returns for an intelligent high-tech employee. "This was a smart person with nothing more on the returns than wages, interest, dividend, mortgage interest, taxes and contributions — and there were significant errors on every year," Taylor says. "If someone is detail-oriented and good at following directions, then they could probably handle a basic return. Otherwise, they should hire a pro."

5. Your life hasn't changed from the previous year. I've noticed that many of my clients first come to me when their lives change. They may be getting married, getting divorced, buying investment property, selling a house that had a home office, starting a business or pulling money out of retirement plans — the key is that something new and different is happening in their lives and it affects their tax returns. You're a better do-it-yourself candidate if there was nothing new in your life last year and your return is likely to look pretty similar to what you filed in previous years.

6. Money is more important to you than time. Ultimately, the issue for some people becomes simply one of time. They are capable of doing their own returns, but would rather pay a tax pro and have those several hours or days they might spend on their returns available for other things.I understand that sentiment. I know how to do a lot of repairs around the house and how to work on my own computer, but I'll often spend the money on a professional repairman or tech expert instead. I figure a pro who does something all the time is likely to know some things I don't and will do the work faster and better than I can. The money I spend is more than made up for by the time that gets freed up for other things.But remember, I'm biased.