While the IRS argued for legislative reinstatement of the partial-payment option, approval is not automatic. Taxpayers who request a partial-payment installment agreement must provide detailed financial information, including data on equity assets, that the IRS will verify. Plus, the IRS will review the arrangement every two years to determine whether the taxpayer's financial status has changed, and if it has improved, the amount of installment payments could increase or the agreement could be terminated.

Regardless of whether you pay your tax bill in full or partially via an installment agreement, keep in mind that paying over time, even to Uncle Sam, will cost you more. The IRS charges a one-time fee of $105 unless you arrange to have your installment payments made via direct debit from your bank account.

The fee drops to $52 for direct debit agreements. Some lower-income taxpayers could pay a reduced fee of $43, which was the previous user fee for all installment agreement applicants.

If you want to apply for an installment arrangement, the IRS now accepts online applications.

Let's make a deal
What if you can't pay off your tax bill, in whole or part, in three years or five years or even longer? Then it might be time to negotiate.

The IRS might be willing to accept an offer in compromise, or OIC, a lump-sum payment you offer to make that is less than the total amount of tax you owe. In these cases, the agency hopes to get some taxpayer money sooner than it would after years of costly collection efforts.

The key here is that the amount must reasonably reflect your ability to pay. It's not merely haggling to get your tax bill reduced. In fact, the IRS is stepping up its efforts to weed out taxpayers who use the OIC route merely to delay paying their bills. Since Nov. 1, 2003, any taxpayer making a reduced payment offer has needed to include a $150 application fee with the request. The agency hopes this means that it will hear only from folks who truly need the negotiated bill.

The IRS will review your financial situation and future income potential to determine whether your offer is appropriate. Be warned, however. Uncle Sam says this program was designed only for extreme cases, and few filers will qualify for the program under the terms the IRS would like. If you believe your situation does indeed meet the requirements, you need to file two forms: Form 656, Offer in Compromise, and Form 433-A, Collection Information Statement.

You must also submit the $150 application fee along with Form 656-A, Income Certification for Offer in Compromise Application Fee and Payment. (The fee is waived for filers who have little or no income. They can claim a poverty exception when they file Form 656-A.) If you don't send this form along with your fee, the IRS will return your offer application "without further consideration."

If you submit everything as required, and the IRS determines you do not meet the qualifications and rejects your offer, you are out $150. But if the agency accepts your offer, your fee will go toward your new payment amount.

Then the IRS wants even more upfront. Your offer must include a 20 percent payment for lump-sum cash payment offers or your first installment payment if you're seeking a periodic payment plan.

The IRS also says it's willing to work with taxpayers who are having a hard time in this economy making their payments, tax or otherwise. The key is to call the IRS and let the agency know you need help meeting your tax obligations. If you just ignore your bill, the agency will continue to assess penalties and interest charges.

Regardless of which payment method you choose, make your decision now. Delay will only compound your financial and tax problems. And try to pay something. By sending in any amount when you file your return, at least you'll ultimately reduce your interest and penalty charges.

Freelance writer Kay Bell writes Bankrate's tax stories from her Austin, Texas, home. She also writes two tax blogs, Eye on the IRS for Bankrate and Don't Mess With Taxes, and is the author of the book "The Truth About Paying Fewer Taxes."