How to Fill Out Colorado Form 104PN: Income Grid, Percentage, and Tax

To fill out Colorado Form 104PN, you work line by line through every category of income on your federal return, entering the full federal amount in one column and the Colorado-connected portion in a second column, then let the form divide the Colorado total by the federal total to produce an apportionment percentage that scales your Colorado tax down to the share actually tied to the state.1Colorado Department of Revenue – Taxation. DR 0104PN – Part-Year Resident/Nonresident Calculation Schedule The form attaches to your DR 0104 and is required any year you file as a part-year resident or nonresident.

The form has three working parts: a short residency header, a two-column income grid that runs most of the page, and an apportionment calculation at the bottom.2Colorado Department of Revenue. Colorado Individual Income Tax Filing Guide Each part depends on the one before it, so the order on the form is the order to work in.

What to Have in Front of You

Every figure on the 104PN ties back to a specific line on your federal return, so a completed federal Form 1040 is non-negotiable. Pull together your W-2s and 1099s (NEC, MISC, INT, DIV, R), and pin down the exact month and year you moved into or out of Colorado — the form asks for beginning and ending residency dates. For wages, Colorado-source income depends on where you were physically working, not where the employer sits, so pay stubs or employer records showing work location matter.3Colorado Department of Revenue. Income Tax Topics: Part-Year Residents and Nonresidents If you also paid tax to another state on any of the same income, keep that return handy; you’ll submit a copy with your Colorado filing.

One residency note before you start. Colorado treats you as a resident if you’re domiciled here or if you keep a permanent home here and spend more than six months of the year in the state.4Colorado Public Law. Colorado Code 39-22-103 – Definitions – Construction of Terms A person can only have one domicile at a time, and intent carries more weight than a raw day count. Someone in Colorado on a temporary assignment may still be domiciled elsewhere if they plan to return.5Department of Revenue. 1 CCR 201-2 – Income Tax

Lines 1 Through 3: Residency Status

Lines 1 and 2 ask you (and your spouse, on a joint return) to check one box: full-year nonresident, part-year resident, or full-year resident. Part-year residents also enter the beginning and ending month and year of Colorado residency. Line 3 asks which federal form you filed, usually Form 1040.

Lines 4 Through 20: The Two-Column Income Grid

This is the heart of the form. Each income category gets two entries: a “Federal Information” column holding the total from your federal return, and a “Colorado Information” column holding the portion connected to Colorado. The rule for the Colorado column is a two-part test. First, was the income received while you were a Colorado resident? If not, was it derived from a Colorado source? If either answer is yes, it belongs in the Colorado column.6Colorado Department of Revenue. Colorado Form 104PN Part-Year Resident/Nonresident Tax Calculation

Work through the lines in order:

  • Lines 4–5 (Wages): Federal column takes total wages from Form 1040, line 1z. Colorado column takes only wages earned while physically working in Colorado or while you were a Colorado resident. Employer-reimbursed moving expenses go in the Colorado column only if the move was into the state.
  • Lines 6–7 (Interest and Dividends): Federal column takes total taxable interest and ordinary dividends. Colorado column takes amounts received while you were a Colorado resident, plus any derived from real or tangible property located in Colorado.
  • Lines 8–9 (Unemployment/FAMLI): Federal column takes the federal amount. Colorado column takes Colorado unemployment or FAMLI benefits, plus benefits from another state received while you were a Colorado resident.
  • Lines 10–11 (Capital Gains and Losses): Federal column takes total gains and losses. Colorado column takes gains or losses recognized while you were a Colorado resident, or from property located in Colorado.
  • Lines 12–13 (Retirement Income): Federal column takes IRA distributions, pensions, annuities, and Social Security from your federal return. Colorado column takes amounts received during the part of the year you were a Colorado resident. Retirement income received by nonresidents is generally not Colorado-source income under federal law.3Colorado Department of Revenue. Income Tax Topics: Part-Year Residents and Nonresidents
  • Lines 14–15 (Business and Farm Income): Federal column takes total business and farm income or loss. Colorado column takes the portion earned while a resident or from Colorado sources.
  • Lines 16–17 (Supplemental Income): Rental income, royalties, and pass-through income from partnerships, S corporations, and trusts. Colorado column takes amounts from Colorado sources or received while a Colorado resident.
  • Lines 18–19 (Other Income): Catch-all for remaining federal income, allocated the same way.

Two edge cases trip people up. Income from intangible property such as stocks and bonds is only Colorado-source income if it’s connected to a business carried on in Colorado; otherwise it follows your residency. And if one spouse on a joint return is a full-year Colorado resident, that spouse’s entire income goes in the Colorado column no matter where it came from.6Colorado Department of Revenue. Colorado Form 104PN Part-Year Resident/Nonresident Tax Calculation

Lines 21 Through 34: Additions, Subtractions, and the Percentage

Once each column is totaled, the form walks you through Colorado-specific additions and subtractions that modify your federal adjusted gross income. On line 26, enter any additions reported on your DR 0104, with four exceptions: the state income tax addback, the gross conservation easement addback, the federal deduction addback, and the qualified business income deduction addback. On line 30, enter subtractions from your DR 0104AD, except any qualifying charitable contribution subtraction.7Department of Revenue – Taxation. Income Tax Topics: Part-Year Residents and Nonresidents The result is your “modified federal adjusted gross income” in each column.

The form then divides your Colorado modified adjusted gross income by your total modified federal adjusted gross income to produce the apportionment percentage. It can exceed 100% in unusual situations, but it cannot drop below zero.

How the Percentage Becomes Your Tax

Colorado’s flat income tax rate is 4.40%, set by Proposition 121 starting with the 2022 tax year.8Department of Revenue – Taxation. Individual Income Tax Frequently Asked Questions Rather than applying that rate only to the Colorado column directly, the state first computes what your tax would be as a full-year resident on your entire federal taxable income, then multiplies that full-year tax by your apportionment percentage.9FindLaw. Colorado Code 39-22-110 – Apportionment of Tax for Part-Year Residents and Nonresident Individuals

A concrete run-through: you earned $100,000 total, and $40,000 belongs in the Colorado column. The apportionment percentage is 40%. If the tentative full-year tax on $100,000 (after deductions) is $3,740, multiplying by 40% gives $1,496 as your actual Colorado tax. The reason the state doesn’t simply charge 4.40% on the $40,000 directly is that deductions apply against your full income rather than only the Colorado slice, and this method preserves that effect.

Attaching the Form and One Note on Other-State Credits

Form 104PN is not filed on its own. Attach it to your DR 0104 and submit them together.1Colorado Department of Revenue – Taxation. DR 0104PN – Part-Year Resident/Nonresident Calculation Schedule If you have income from more than one state and are claiming a credit for taxes paid to another state, you must file electronically.10Colorado Department of Revenue. DR 0104CR – Individual Credit Schedule

One boundary worth flagging because the 104PN looks like the place to handle it, and isn’t: a credit for taxes paid to another state is claimed on Form DR 0104CR, not on the 104PN.11Colorado Department of Revenue – Taxation. DR 0104 Booklet – Individual Income Tax Filing Booklet The DR 0104CR instructions also note that part-year residents “generally do not qualify” for the credit, because the 104PN apportionment already limits your Colorado tax to Colorado-connected income.10Colorado Department of Revenue. DR 0104CR – Individual Credit Schedule It matters mainly when two states claim taxing rights over the same income, such as remote work for a Colorado employer while living in another state that also taxes that income.