More than 13 million returns have been filed this tax season by people e-filing from the comfort of their own homes, up from just over 11 million for the same period last year. Were you one of the 13 million -- or are you still working on your tax return?

If you're not done yet, great news -- since April 15 falls on a weekend, you've got a couple of extra days to finish this year. You have until Monday April 17.

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So, just relax. Take a deep breath and calm down. Start focusing on your tax mantra -- one record at a time. One record at a time. One record at a time. Remember, even if that entire rat's nest of records doesn't contain the one or two critical things you need to finish your tax return, you can always get an extension. And this year, that extension is good for six months, instead of four. So you have plenty of time.

Still breathing deeply? Feel better? Good.

If you think you're going to need an extension, plan for it now. There are only two extension forms this year to cover all people and all businesses and other tax-paying entities.

People get to use Form 4868. Form 4868 will give you another 6 months, until Oct. 15.

Businesses, trusts and others get to use Form 7004. Form 7004 will also give you another 6 months, until Oct. 15, if you're a calendar-year entity.

When you fill it in, if you think you'll owe money when you finally file your tax return, be sure to fill in the balance you expect to owe. Don't just put an amount that you can afford to pay. Otherwise, IRS might reject your extension because it wasn't a true representation of your total tax liability.

Even though it's an automatic extension on filing, it's not an automatic extension on paying. IRS is looking for the payment on April 17.

If you can't afford to pay now, don't worry. The interest rate charged on unpaid taxes is fairly low this year -- 7% per year. And the underpayment penalty, if you get an extension, is only a quarter of a percent per month, until the final due date of the return. That's only a total of 5% for the whole six months.

By filing the extension, you've already cut the nonfiling penalties in half, from 0.5% per month.

Diane Laux of Military.com in San Francisco says that service members in a combat zone during tax season get an automatic extension to file their taxes. Service members have six months from the time they leave the combat zone to file. Service members who are stationed elsewhere overseas have a two-month extension to file once they return -- even if they haven't filed for a formal extension.

Some states accept the IRS extension, but many don't. You can find your state's forms online at www.taxadmin.org and rules here.

K-1s Must Match

Allyson Hayes, senior tax manager in the New York office of BDO Seidman LLP, says that the IRS has greatly enhanced its K-1 matching process so that it is now fully computerized. If you're a member of a partnership, S-corporation, limited liability corporation or trust, be sure to pick up every item on your K1. Why? Because if you don't the IRS will!

Be sure to give your tax preparer the phone number of your investment professional, advises Susan Hirshman, planning strategist at J.P. Morgan Funds. Your investment professional can help provide the basis, or tax cost, of all the stocks you sold. They can track down missing K-1s, if your investment is held with your broker.

If the K-1 investment isn't held by your broker, perhaps it's a good idea to give the manager's contact numbers to your tax professional. Even if they can't get the K-1 yet, perhaps your tax pro will have a good estimate to use in determining if there's a balance due for your extension.

Save some money, save some taxes

Save, save, save, says John Diehl, certified financial planner and vice president at The Hartford. Diehl says you should be contributing as much as possible to a variety of government and employer-sponsored tax deferred retirement vehicles, including 401(k)s, IRAs and 403(b)s.

If you've taken full advantage of these plans, you might consider other tax-advantaged savings vehicles such as a tax-deferred annuity or tax-exempt municipal bonds.

Diehl suggests that it's never too early for an income plan. Lines 15, 16 and 20 of your Form 1040 tax return show income drawn from IRAs, pensions and other annuities and Social Security. Do you have an idea of where your retirement income will come from? If you're already retired, are you taking income in the most tax efficient way?

If you take the time to review your retirement account draws, you may be able to increase them tax-free if you have high medical expenses or other deductions or losses to absorb the income. Many people overlook this, especially when a taxpayer is ill and no one is watching over finances.

Remember to fund

Speaking of IRA's, if you filed earlier, taking a deduction for an IRA contribution, counting on getting the refund in time to fund the IRA ... remember to fund it. If the refund money hasn't arrived, borrow some money for a couple of days to make the deposits. It's generally cheaper to pay the cash advance fees on your credit card than to miss funding an IRA you deducted on your tax return.

Incidentally, you don't need to call your tax professional or online filing company to track down your refund. Just go to IRS's Where's My Refund page, online here. You'll find out the status right away.

Be sure to check your state's Web site to see if they have something similar.

Remember to pay

One of the problems you're apt to face when you file your tax returns electronically if you have a balance due is that you forget to pay the taxes due. Since you're not sending in the return, there's nothing to trigger your memory about making that payment with the 1040-V.

Also, remember to make the estimated payments. Your tax professional gave you a set of vouchers. Or IRS sent them to you, if you fit the profile last year. Pull out the 1040-ES voucher labeled 2005 Payment Voucher 1. Check out the forms here.

Have you ever heard of a tickler file? It's a file you look into each day, or week or at the beginning of each month. It contains notes, messages or other to-do information. Drop yourself a note in your tickler files in June, September and January, so you can remember to make all the estimated payments on time.

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