What Is Form 104 Colorado and Who Needs to File It?

Form 104 is a document used in Colorado’s state tax system, serving as the primary income tax return form for individuals and entities with financial connections to the state. Understanding who is required to file ensures compliance and avoids penalties.

This article examines the key aspects of Form 104, including filing requirements, residency classifications, income considerations, deadlines, submission methods, and required documentation.

Filing Criteria

Filing requirements for Form 104 in Colorado depend on income levels and residency status. For the 2024 tax year, individuals with a gross income exceeding $5,500 must file. This applies to residents, non-residents with Colorado-sourced income, and part-year residents whose income during their time in Colorado meets this threshold.

Corporations operating in Colorado must file if they have any income from state sources, regardless of the amount. This includes both domestic and foreign corporations. Partnerships and S-corporations must file informational returns if they earn Colorado-sourced income. Trusts and estates with taxable income in Colorado are also required to file, with fiduciaries responsible for ensuring compliance.

Residency Classification

Colorado categorizes taxpayers as residents, non-residents, or part-year residents, each with specific tax obligations. A resident maintains a permanent home in Colorado and spends more than 183 days in the state during the tax year. Residents are taxed on their worldwide income, while non-residents are taxed only on income earned from Colorado sources, such as wages or rental income.

Part-year residents split their income between their resident and non-resident periods, requiring careful records to accurately allocate income. The Colorado Department of Revenue offers guidance on sourcing rules to assist with accurate reporting.

Income and Deductions

Filing Form 104 requires understanding Colorado’s tax regulations and their connection to federal tax laws. Taxable income includes wages, salaries, tips, dividends, interest, and rental income. Colorado uses federal Adjusted Gross Income (AGI) as the starting point for state tax calculations.

Taxpayers can claim a standard deduction, which matches federal amounts for 2024: $13,850 for single filers and $27,700 for married couples filing jointly. Alternatively, taxpayers can itemize deductions, including state-specific options such as the Colorado Child Care Contribution Credit or medical expenses exceeding 7.5% of AGI.

For businesses, deductions are allowed for ordinary and necessary expenses, such as salaries, rent, and utilities. Partnerships and S-corporations allocate income and deductions to partners and shareholders to ensure accurate reporting.

Filing Deadlines

Filing Form 104 on time is crucial to avoid penalties. For individuals, the deadline aligns with the federal tax filing date, usually April 15. If this date falls on a weekend or holiday, the deadline moves to the next business day. For 2024, taxpayers should plan for April 15, with adjustments if necessary.

Businesses and fiduciaries have different deadlines based on their fiscal year. Corporations using a calendar year must file by April 15, while those with a fiscal year-end must file by the 15th day of the fourth month after their year-end. Partnerships and S-corporations file by March 15. Extensions are available for filing but do not extend the deadline for tax payments, which must be estimated and paid by the original due date to avoid penalties.

Methods of Submission

Colorado taxpayers can file Form 104 electronically or on paper. Electronic filing (e-filing) is recommended for its speed and accuracy. The Colorado Department of Revenue’s online portal, Revenue Online, allows taxpayers to submit returns and track their status. Many third-party tax preparation software programs also integrate with Colorado’s e-filing system.

Paper filing is an option for those who prefer it, but processing times are longer. Taxpayers filing by mail are encouraged to retain proof of mailing, such as a certified mail receipt, to confirm timely submission.

Required Documentation

Accurate documentation is essential for completing Form 104. Taxpayers must organize records to support the income, deductions, and credits reported on their return, reducing the risk of audits or penalties.

For individuals, required documents include W-2 forms for wages, 1099 forms for other income, and records of prior-year state tax refunds. Supporting documents for deductions or credits, such as receipts for charitable contributions, medical expenses, or childcare costs, are also necessary. Taxpayers with investments or rental properties should include statements for capital gains, losses, rental income, and related expenses.

Businesses and fiduciaries have additional requirements. Corporations must provide financial statements, such as income statements and balance sheets, to verify reported income and deductions. Partnerships and S-corporations must prepare Schedule K-1 forms for each partner or shareholder, detailing their share of income and deductions. Trusts and estates should maintain records of distributions to beneficiaries and income earned during the tax year. Thorough record-keeping is critical, as the Colorado Department of Revenue may request documentation to confirm return accuracy.