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Colorado State Taxes and CO Income Tax Forms

Colorado State Income Taxes for Tax Year 2020 (January 1 - Dec. 31, 2020) can be prepared and e-Filed now along with an IRS or Federal Income Tax Return (or you can learn how to only prepare and file a CO state return). The Colorado tax filing and tax payment deadline is April 15, 2021. Find IRS or Federal Tax Return deadline details.

efile Colorado state tax return
"The Centennial State"

If you file a tax extension you can e-File your Taxes until October 15, 2021 without a late filing penalty. However, if you owe Taxes and don't pay on time, you might face late tax payment penalties. Tip: File on time, even you can't pay on time, as the late filing penalties are higher than the late payment penalties. Estimate your penalties with our free PENALTYucator tool.

eFile.com makes it easy for you to e-file your IRS and Colorado State Tax Return (e.g resident, nonresident, or part-year resident returns). However, the IRS and the respective State Tax Agencies require you to e-file a Federal Income Tax Return at the same time you e-file a State Tax Return. This is not an eFile.com policy but an IRS and State Agency policy. Thus, technically you cannot e-File anywhere - not just eFile.com - a Colorado Tax Return without also e-filing the associated IRS Tax Return. But there is good news, please read on.

Detailed instructions on how you can only prepare and mail in - not eFile - a Colorado 2020 Tax Return - here via eFile.com. However, you must download/print and sign the forms and mail them to the Tax Agency.

Where Is Your Colorado Tax Refund Money
Step 1: Sign into your eFile.com account and check acceptance by the Tax Agency.
Step 2: Check your Colorado Tax Refund Status.
Where is Your IRS Refund?
Step 1: Sign into your eFile.com account and check acceptance by the IRS.
Step 2: Check your IRS Tax Refund Status.
Colorado Income Tax Extension
How to correct a rejected Tax Return
If your CO Income Tax Return was rejected by the CO Tax Agency - not eFile.com - instructions on how to correct a rejected Colorado Tax Return.
Colorado, IRS Late Filing, Tax Payment Penalties
1. Late Filing Penalty:This penalty is $5 or a percentage of the unpaid tax equal to 5% (whichever is greater) for each month the tax return is filed after Tax Day, plus ½% for each full or partial month the tax remains unpaid. It will not exceed a total of 12%.
2. Late Payment Penalty: This penalty is the same as the late filing penalty.
3. IRS Penalties: Calculate and Estimate your potential IRS Income Tax Return Penalties.
CO Tax Return Mailing Addresses
Find various Colorado Mailing Addresses for tax returns, tax amendments, and tax payments.
Colorado Income Tax Brackets
Colorado Income Tax Forms
Colorado Unemployment Benefits
Colorado fully taxes unemployment income at the state level.


Start Federal and Colorado Tax Returns


2021 Colorado Income Tax Return Filing Deadlines By Tax Year

The majority of deadlines listed here are for Tax Year 2020. Some apply to upcoming Tax Years and some are IRS or Federal deadlines.

April 15, 2021 
Tax Year 2020 Income Tax Return
Original Deadline to prepare and e-File a Colorado Income Tax Return. You have until October 15, 2021 to complete and e-File your Federal Income and Colorado State Income Tax Return. eFileIT*
April 151 2021 (Deadline has passed. However, Colorado does offer an automatic tax extension.)
2020 Income Tax Extension
October 15, 2021
Tax Year 2020 Income Tax Return after the automatic April 15, 2021 Colorado Tax Extension
Last day to eFile a 2020 Colorado State Income Tax Return for Tax Extension Filers and late eFilers. You can only eFile (to file by paper see below) Colorado Income Tax Return together with an IRS Tax Return.eFileIT*
October 15, 2021 via mail-in Forms. Forms incl. Mailing Address are listed below.
Tax Year 2020 Income Tax Return after the automatic April 15, 2021 Colorado Tax Extension
Deadline for taxpayers who got an automatic CO Tax Extension to file their Colorado Income Tax Return by mail-in Forms - the Forms incl. mailing addresses are listed below - is October 15, 2021. (Optionally: the eFileIT* deadline is Oct. 15, 2021). Instructions on how to only - without the IRS return - prepare and file a Colorado State Income Tax Return on eFile.com.
Tax Amendment for All Tax Years
IRS Due Dates
IRS Tax Return, Extension, Amendment Deadlines
2021, 2022, etc.
Other State Tax Return, Extension, Amendment Deadlines
Select respective State Tax Return Deadlines.
2021, 2022, etc.
IRS Federal Income Tax Return, Amendment, Extension Deadlines
April 15, 2024
2020 Colorado Income Tax Return Refund. IRS Tax Return Refund Claim Deadline
The last day to file - you will not face late filing penalties - and claim your 2020 Colorado Income Tax Return Refund. This deadline does not apply if you owe 2020 Income Taxes.

E-File These 2020 Colorado State Tax Forms

Prepare and e-File these 2020 Colorado State Forms in conjunction with your Federal and State Income Tax Return. As you proceed through the tax interview on eFile.com, the application will select the correct state forms for you. You can also select tax forms individually. All these forms will then be e-filed by you to the CO State Tax Agency. Instructions on how to only prepare a State Income Tax Return.

eFileIT Now*
Form 102
Claim for Refund on Behalf of Deceased Taxpayer
Form 104
Individual Income Tax Return
Form 104CR
Individual Credit Schedule/Credit for Income Tax Paid to Another State
Form 104EP
Estimated Income Tax Payment Voucher
Form 104PN
Part-Year Resident/Nonresident Tax Calculation Schedule
Form 204
Computation of Penalty Due Based on Underpayment of Colorado Individual Estimated Tax
Form DR0900
Individual Income Tax Payment Voucher
Form DR1366
Enterprise Zone (EZ) Carryforward Schedule 2
Determines your paycheck CO Tax Withholding amount per employer.
Step 1: Complete and submit to your employer(s).
Step 2: Estimate, Calculate your IRS Tax Withholding now.
Cannot be e-Filed. Mail-in only.

* Due to IRS and State Tax Agency tax data sharing and validation requirements, you can only e-file a State Income Tax Return while also e-filing a Federal Income Tax Return. This is not an eFile.com created policy, but all online tax web sites have to adhere to this IRS/state issued tax data sharing policy. You can however prepare all 44 State Income Tax Returns on eFile.com if you have already e-Filed or filed your IRS return. Instructions on how you can ONLY prepare and file State Income Tax Return(s). Only on eFile.com can you prepare, file or e-file unlimited State Tax Returns for one low price and not pay for each State return like you would do on H&R Block® vs. TurboTax®. Dare to Compare Now.

Automatic Colorado State Income Tax Extension

For Tax Year 2020, you can no longer e-File an extension for Colorado Tax Returns. Unlike the IRS, Colorado grants all taxpayers an automatic 6-month extension (which means you do not file an extension form in Colorado) of time to file penalty free beyond the April 15, 2021 deadline. The extended e-File and paper filing deadline is October 15, 2021.  Keep in mind however, a Colorado or IRS tax extension does not extend the due date to pay owed taxes or income tax liabilities penalty free.

If you owe Colorado and/or IRS income taxes and don't pay them by Tax Day, you will be charged Colorado and IRS late tax payment penalties. Calculate and estimate IRS late payment penalties. If you expect to owe taxes, and you are going to take advantage of the Colorado automatic extension of time to file, you should still pay what you owe online at Colorado Revenue Online.  However, if you want to pay by check or money order, you must submit Form Extension Payment Tax Form DR0158-I before April 15, 2021.

To avoid the Colorado penalty for late payment, you must pay at least 90% of what you owe by April 15, 2021. Any remaining balance due will only be subject to interest fees, as long as the rest of the tax owed and the return is by the extension deadline, October 15, 2021.

Instructions on how to eFile an IRS tax extension for free on eFile.com by April 15, 2021.

The extended IRS/Colorado eFile deadline is Oct. 15, 2021 - eFileIT*. If you plan to file or mail-in a Colorado tax return on paper - the Forms and Mailing Address are below - your due date is Oct. 15, 2021.

Colorado State Tax Payment Options
You can select one of these payment options either after you have e-filed or filed your 2020 Colorado Tax Return. Alternatively, you can pay Colorado income taxes here prior to filing (e.g in the case of an extension). Plus, you can make online Colorado tax estimate payments for next tax year. If you eFiled your taxes and pay online, you do not have to send in Colorado paper forms (e.g. payer tax return, extension form, or tax estimate form). 
Create an account with Colorado Revenue Online to submit your payment. Make sure you have a copy of your most recently filed and accepted Colorado Tax Return when you create your account. If you already have an account, log into your account.
Check the status of your direct payment
This is a free option if you register for Electronic Funds Transfer.
Submit a tax payment through Colorado's Revenue Online site. When you're on the site, select the "Individual Income Tax" as the Account Type, then follow the on-screen prompts to enter and submit your information (e.g. ID Type, ID, Filing Period, Payment Type).
Use this payment option if you want to pay your tax payment via your credit or debit card. There is a service fee of $0.75 plus 2.25% of the payment amount.
Check or Money Order with Form DR0900
Complete voucher Form DR0900 and attach it to your check or money order payable to "Colorado Department of Revenue". Write your Social Security number or ITIN, and "2020 DR 0104" on the check. Mail them to the Form DR0900 address below.
Use this payment option if you wish to submit your payment via check or money order in the mail. 
Estimated Tax Payment Options
Choose one of these options: 1) Create an account with Colorado Revenue Online to submit your estimated payment (or if you already have an account, log into your account and choose "Estimated Payment"). In your account, you can pay by EFT, view your account history, and receive messages that the state tax agency accepted your payment. 2) Pay via E-Check by sending tax payments from your bank account to Colorado Department of Revenue.  However, there is a $1 service fee for paying by E-Check.  3) Pay via credit or debit card through Colorado Revenue Online (choose the "Debit or Credit Card" and choose "Estimated Payment" as your payment type). Be aware there is a service fee of $0.75 plus 2.25% of the payment amount if paying by Debit or Credit Card. 4) Complete voucher Form DR 0104EP. Attach a check or money order for the tax period payable to "Colorado Department of Revenue". Write your Social Security numbers and "2020 DR 0104EP" on the check or money order. Mail the voucher and check/money order to the Form DR 0104EP here.
Use one of these payment options if you want to submit estimated taxes rather than submit all your taxes owed at once. 
Many of these online IRS tax payment options can be used before or after you e-Filed your Income Taxes. You can pay tax extension and tax estimate payments. For estimate payments, you do not have to submit a form. Extension you can eFile on eFile.com for free.
These payment options are independent from you preparing and eFiling your tax returns on eFile.com. eFile.com offers these payment options for the convenience of all tax payers.


Colorado Tax Return, Amendment, etc. Mailing Addresses
Addresses to mail Colorado Tax Returns, Amendments, Extensions, or Tax Payments.
CO Tax Return or Amended Tax Return: Address if you expect a Tax Refund on your Tax Return
Colorado Department of Revenue
Denver, CO 80261-0005
CO Tax Return or Amended Return: Address if you owe Taxes and include payment.
Colorado Department of Revenue
Denver, CO 80261-0006
CO Tax Extension: Address if you owe Taxes and include payment with Form DR0158-I Tip: Make Tax Payments online and you will not have to mail in Form DR0158-I. See above.
Colorado Department of Revenue
Denver, CO 80261-0008
CO Tax Payment: include tax payment Form DR0900
Colorado Department of Revenue
Denver, CO 80261-0008
CO Tax Estimate Payments: include tax year 2020 Form DR 0104EP.
Colorado Department of Revenue
Denver, CO 80261-0008


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