It's that time of year again. If you haven't already started the laborious task of filing your taxes, here's a reminder: The due date is April 17.

Of course, you can get an extension of up to six months from the Internal Revenue Service. However, filing for an extension with the IRS won't help you defer payment if you owe money.

If you are having a hard time scraping up the cash to pay the taxman, you have a few options. However, it is essential to file your tax return before the deadline. If you don't file, you will be penalized and owe interest. Failure to file on time can cause the amount you owe to increase by up to 100%.

Here are four options to help you when you may not be able to pay right now:

1. Set up monthly installments

If you owe less than $25,000 and agree to pay off the balance in five years or less, you can request more time and set up a monthly automatic payment plan. You can fill out an Online Payment Agreement form, search “installment agreements” at or call 800-829-1040.

If you are able to pay your tax bill in full within 120 days, you can avoid the fee associated with setting up the installments and you won't owe Uncle Sam any interest. If you can't pay it off in 120 days, the costs start to pile up. The setup fee is $52 for a direct debt and $105 for a standard agreement or payroll deduction agreement. Low-income taxpayers can qualify for a $43 fee.

Additionally, if you don't pay the tax bill in full within 120 days, you have to pay interest on the amount you owe. As of April 2012, that rate stood at 3%.

2. Pay by credit card

The IRS will take money in many different ways, and that includes via credit card. If you don't have enough cash on hand, paying with plastic can buy you a little more time. However, there are downsides to this method.

First, you wil have to pay an administrative fee of that can range up to more than 3% of the transaction. That's because unlike many retailers, the IRS doesn't eat the cost of credit card processing; it passes it along to the consumer. That means if you owe $5,000, you may pay an extra $150 (3% of $5,000) just to pay by card. No matter what rewards credit card you have, you probably aren't going to break even on the transaction.

If you still can't scrape up enough cash when the monthly credit card bill comes in, your costs will jump even more because you will have to pay interest to the credit card company.

Finally, if you eat up too much of your available credit, it can hurt your credit score. That's because your credit utilization rate -- the amount of debt you have compared to the amount of credit you have available -- is a major factor used in determining your credit score. Experts typically recommend not using more than 30% of your available credit. If you use more than that, you may have to pay a higher interest rate if you want to borrow.

3. Request an 'offer in compromise'

If you are confident you will never be able to pay off your tax bill, you can request an offer in compromise, in which the IRS allows you to settle your tax debt for less than the full amount you owe.

However, you must convince the IRS that you have exhausted every resource you have to pay the bill and have little chance to earn enough money to pay the debt in the future. Typically, unless you are elderly or disabled, it is extremely difficult to obtain a compromise.

4. Try a partial payment installment agreement

In this agreement, the debtor can pay monthly installments for a set period of time and once the collection period ends, the excess debt is forgiven. While this is still extremely difficult to obtain, it is slightly easier than a compromise.

However, it has one major caveat that is not present with the offer in compromise. Each partial payment agreement must be reviewed every two years. In that review, the IRS will look at whether there were any significant increases in your income or assets. If there were, the IRS would be able to either demand payment of your remaining tax debt in full or increase the amount you're required to pay each month. The terms of the offer in compromise, on the other hand, are final -- assuming you to continue to make payments on a timely basis.

For either the offer in compromise or the partial payment installment agreement, the IRS requires detailed financial information, so it is vital to consult an experienced tax attorney before you submit these offers to the IRS. They can look at your information, give advice and let you know if your claim is plausible.

The Investing Answer: If you need a little more time to get together the cash to pay your tax bill and you owe less than $25,000, your best bet is to go ahead and file your taxes then set up a monthly installment agreement and pay off the total in 120 days or less. It requires a little bit of paperwork and likely some long hold times on the phone, but you will incur fewer penalties and have your bill paid.

[Learn more: 20 Surprising Facts Most Taxpayers Don't Know]