State Tax Debt

Colorado Back Taxes Payment Plan: How to Set One Up (2025)

By Angeline Balsitis, EA · Reviewed by Melissa Ly, Chief Tax Officer · Updated August 7, 2025 · Editorial Standards

Why you owe Colorado back taxes

A Colorado back taxes balance usually starts in one of a few ways. You filed a Colorado return and didn't pay the full amount. You under-withheld or skipped estimated payments and came up short at tax time. You never filed a state return, so the Colorado Department of Revenue (CDOR) estimated your tax for you. Or the IRS adjusted your federal return — and because Colorado income tax is based on your federal income, the state followed with a bill of its own.

Colorado is a flat-rate income tax state, so the math is simpler than the federal system. But the collection tools are real. The Department of Revenue is a separate agency from the IRS, with its own notices, its own deadlines, and its own power to file liens and garnish wages. You can read more about your options directly from the Colorado Department of Revenue, Taxation Division.

What happens if you ignore a Colorado tax bill

Like the IRS, Colorado's collection process is automated and moves in stages. Ignore each notice and the next step carries more weight:

1. Notice of Deficiency — the state says you owe. You have about 30 days to protest before it becomes final.
2. Notice of Final Determination / balance due — the assessment is locked in. Penalties and interest keep building.
3. Judgment / state tax lien — Colorado can record a lien that attaches to your property and shows up when you sell or refinance.
4. Garnishment and levy — the Department of Revenue can garnish wages, levy bank accounts, and keep your Colorado refund. The state can also intercept your federal refund through the Treasury Offset Program.

The point isn't to scare you — it's that delay is the only thing that turns a manageable bill into garnished paychecks. A payment plan stops this sequence in its tracks.

How a Colorado back taxes payment plan works

Colorado's payment plan is the state version of an IRS installment agreement: you pay the balance over time in monthly amounts instead of all at once. Here's what to expect.

• Where to set it up: through Revenue Online at tax.colorado.gov, or by calling the Department of Revenue's collections section. Many taxpayers can request a plan online without a long phone call.
• What you propose: a monthly payment you can actually afford. The state generally wants the balance paid within a reasonable period and may ask for a larger down payment on bigger debts.
• What keeps it alive: pay on time every month, and file and pay all future returns. Missing a payment or falling behind on a new year's taxes can default the plan.
• What it doesn't stop: interest. A plan halts collection, but the balance keeps growing until it's gone. Paying extra toward the principal whenever you can always costs less.
• Direct debit: automatic monthly withdrawals are the simplest way to avoid an accidental missed payment and a defaulted plan.

A quick worked example

Say you owe Colorado $6,000 in back income tax. You can't write a check for the full amount, but you can manage $250 a month. You request a plan in Revenue Online, set up automatic monthly withdrawals, and keep filing on time. Collection stops — no lien, no garnishment. Over roughly two years, the balance is paid off, plus the interest that accrued along the way. The exact total depends on the current statutory interest rate, which is why paying ahead when you can shortens both the timeline and the cost.

If you also owe the IRS

Owing both the IRS and Colorado at the same time is common — especially when a federal change triggered the state bill. They don't talk to each other for your benefit. An IRS plan does not cover your Colorado debt, and a state plan does not touch your federal balance. You'll typically need a separate arrangement with each agency.

On the federal side, the IRS offers a streamlined installment agreement for balances under $50,000 and an online setup process — our walkthrough on how to set up an IRS payment plan online covers it step by step. If you're weighing whether to pay in installments or pursue a settlement, see our guide on the payment plan vs. offer in compromise decision. The same logic applies at the state level: Colorado has its own offer in compromise, but it's reserved for taxpayers who truly can't pay the full balance.

How to respond, step by step

1. File any missing Colorado returns first. The state won't approve a payment plan on years you haven't filed. Get current before you ask for terms.
2. Confirm the balance. Log into Revenue Online and check what the Department of Revenue says you owe by year, including penalties and interest.
3. If a Notice of Deficiency looks wrong, protest it within the 30-day window with documentation — don't let an incorrect amount become final.
4. Choose a monthly amount you can sustain. A payment you can keep up beats an aggressive one that defaults and restarts collection.
5. Request the plan and set up direct debit. Do it before any judgment or garnishment, while you still have the most options.
6. If you owe the IRS too, handle both — and consider a professional review of the order to fix things in, especially with unfiled years or larger balances.

Colorado back taxes questions, answered

This guide is general information, not tax or legal advice for your specific situation. Eligibility for IRS programs depends on individual facts and circumstances; no outcome is guaranteed. For federal payment options, see the IRS payment plans page.

Related: how to set up an IRS payment plan online, the streamlined installment agreement, and payment plan vs. offer in compromise — or browse all guides.