The most common reason is unfiled tax returns. The IRS won’t negotiate how you’ll pay back taxes while you’re still not filing current ones. Before they consider any payment plan, you need to be current on all required returns for at least the past six years.

Current compliance matters too. If you’re self-employed or own a business, you need to be making estimated tax payments for the current year. The IRS isn’t going to set up a plan to pay old debt while you’re creating new debt. If you have employees, payroll taxes need to be current. The IRS takes payroll taxes more seriously than income taxes because that money was withheld from employee paychecks and belongs to the government.

Your proposed payment amount might be too low. For balances under $50,000, the IRS usually approves payment plans automatically if you can pay within 72 months. For larger amounts, you’ll need to submit a Collection Information Statement showing your income, expenses, assets, and liabilities. The IRS has formulas for allowable expenses. If their math says you can afford $1,200 a month and you’re proposing $400, they’ll deny it or counter with a higher amount.

You can only have one installment agreement at a time. If you already have an active payment plan and owe additional taxes from another year, you need to modify the existing agreement rather than apply for a new one.

Defaulting on a previous agreement makes approval harder. If you missed payments on a prior plan, the IRS will be skeptical that you’ll follow through this time. They may require a larger down payment or refuse to reinstate the agreement without evidence that your situation has changed.

Some applications get denied for technical reasons. Wrong form, missing signatures, incomplete financial information. These are fixable problems but they delay the process and add stress.

If the collection statute is about to expire, the IRS may deny a payment plan. They have 10 years from the assessment date to collect. If your proposed monthly payment won’t satisfy the debt before that clock runs out, they may reject the plan and pursue other collection actions like levies or liens.

When you’re denied, you typically have 30 days to appeal. The rejection letter will explain why and what options you have. Often the fix is straightforward. File the missing return. Adjust the payment amount upward. Provide additional financial documentation they requested.

Working with an Enrolled Agent who handles IRS representation can make a significant difference. They know what the IRS looks for, can prepare the required documentation correctly, and can speak directly to IRS representatives on your behalf if complications arise. For a Queen Creek bookkeeper and tax professional like Dan, this kind of advocacy is part of the job. You shouldn’t have to sit through those calls or figure out IRS procedures yourself when you’re already stressed about owing money.