Just what you need. An oversized bunny showing up in the middle of crunch time.

But whether you're spending the weekend hunting down Easter eggs or eating matzo, you better find some time to finish your 2005 tax return. And if you can't peel yourself away from the family fun, seek an extension for that darned filing.

Just know that your tax bill is due by Monday whether you extend or file. Uncle Sam wants his money on time.

But do

something

. If Uncle Sam doesn't receive some correspondence from you by Monday, then you'll get smacked with a late filing penalty of 5% per month, based on the amount of tax you didn't pay on time. That can add up fast.

Big note: Residents of Maine, Maryland, Massachusetts, New Hampshire, New York, Vermont and the District of Columbia have until Tuesday to file their tax returns and pay their bills. That's because they file their returns to the IRS processing center in Massachusetts. And Monday is Patriot's Day, a state holiday, in Massachusetts.

If you decide to throw in the towel and extend, you'll need to file

Form 4868 -- ApplicationFor Automatic Extension of Time To File U.S. Individual Tax Return

.

The good news is that you'll buy yourself an automatic six months, and your return would then be due Oct. 16.

The bad news is that you probably still have to complete your tax return to properly fill out Form 4868.

That's because Form 4868 asks for two numbers from your federal return, the Form 1040. The firstnumber is your total tax liability, which is line 63. The second number is your total payments, which is line 71. To calculate those two, you'll need to fill in all the other lines on the form.

So why bother extending, you ask?

Well, there could be several reasons. You may be waiting on documentation, aka Form K-1, froma partnership you're involved in. These forms usually come in very close to April 17 and you'll need numbers from that document to get your Form 1040 done.

Or, if you're self-employed, you may need time to make your retirement contribution. You have until the due date of your extended return to make your 2005 SEP IRA or solo 401(k) contribution. So if you didn't get around to scraping up the money, the extension buys you more time.

Preparing Your Extension

The easiest way to file your extension is to do it through your

tax-preparation program of choice.

Then, assuming you attempted to prepare your return, all the proper numbers will just flow to the Form 4868 for you. Unfortunately, not all of these tax-prep programs will let you electronically file that extension form. As an example, if you use

Intuit's

(INTU) - Get Report

TurboTax, you'll have to print Form 4868 and mail it, because the program doesn't let you e-file it, says spokeswoman Julie Miller. But you can file for an extension for free using

H&R Block's

(HRB) - Get Report

TaxCut software. If you're using TaxCut Online, it's $19.95 to e-file your extension.

If you do e-file the form, make sure you get a confirmation number from the IRS noting it was accepted. Keep that number with your records.

You can also go to irs.gov and download the form. Print it, fill it out and mail it in. Just be sure to send it via certified mail so you get confirmation that the IRS received it.

If you have tax due and you don't want to mail a check, you can authorize an electronic funds withdrawal from your checking or savings account over the phone. If you choose to do this, make sure you have your adjusted gross income from last year's tax return for verification.

Still Need the Money, Honey

If you don't pay your bill by April 17, the IRS will impose a 0.5% per month penalty.

But if you don't have the cash to pay your tax bill, don't panic. Send your return or extension in anyway and pay as much as you can. Remember, there's a 5% per month penalty for filing your return late, but only a 0.5% per month penalty for not paying the bill on time.

Then consider your options.

You could charge it. The IRS has relationships with two companies that will let you pay with your credit card.

Official Payments and

Link2Gov will let you charge your tax balance using your American Express, MasterCard, Visa or Discover Card. The companies charge a small processing fee, but at least you'll rack up your card points or airline miles. Just make sure the miles outweigh the fees and corresponding interest your credit card will charge if you don't pay your bill on time.

If you don't want to charge your bill, the IRS will let you go on a payment plan.

Uncle Sam will let you decide on your monthly payment amount, so think it through. Once you pick a number, it must be maintained over the life of the agreement.

Then you can opt to have your payment debited from your bank account or deducted from your paycheck. And, of course, you can simply write a check each month. But the first two options at least ensure that you're not going to default on your payments.

You must fill out

Form 9465 -- Installment Agreement Request

for the payments, or create your own written request. Be sure to specify the amount you can pay and the day you wish to make your payment eachmonth. Whichever you choose, attach it to the front of your tax return.

The IRS will respond to your request, usually within 30 days, and say if the request is approved, denied, or if additional information is needed. And, if approved, you'll be hit with a one-time user fee of around $40 that will be added with the first payment.

So try to get your return done this weekend, but if you can't, don't panic. Just extend it and make sure your bill is covered.

Then, enjoy the spring and summer. You won't have to worry about your tax return until the fall. Just makesure it's done before the Big Pumpkin comes.

Tracy Byrnes is an award-winning writer specializing in tax and accounting issues. As a freelancer, she has written columns for wsj.com and the New York Post and her work has appeared in SmartMoney and on MarketWatch. Prior to freelancing, she spent four years as a senior writer for TheStreet.com. Before that, she was an accountant with Ernst & Young. She has a B.A. in English and economics from Lehigh University and an M.B.A. in accounting from Rutgers University. Byrnes appreciates your feedback;

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