Can I file my 2021 2020 taxes with 2023 or I have to file separately?

[Tax Doc]

You can't file or amalgamate previous years with your 2023 return, each return must be filed separately, and there is a plethora of reason for that, like tax tables change due to economic each year, standard deduction changes, there may be some credits which apply for each year that don't, you might have deduction carryovers.  Good news is you can contact Intuit and get the software for those years or contact the IRS at the IRS website, IRS.GOV. 

[xmasbaby0]

Each tax year is separate and must be prepared on the forms for the specific tax year.  No one is preparing a 2023 return now----the returns being prepared online now are for tax year 2022-----the tax year that just ended.   

Only a 2022 return can be prepared online and only a 2022 return can be e-fled.  Earlier years must be filed by mail.

And if you did not file a 2021 return you will have trouble e-filing 2022.  When it asks for your 2021 AGI try using zero.  If zero does not work then you have to print, sign and mail 2022

Online preparation and e-filing for 2019 and 2020 and 2021 is permanently closed.

To file a return for a prior tax year

 If you need to prepare a return for 2019, 2020 or 2021 you can purchase and download desktop software to do it, then print, sign,  and mail the return(s)

https://turbotax.intuit.com/personal-taxes/past-years-products/

You may also want to explore purchasing the software from various retailers such as Amazon, Costco, Best Buy, Walmart, Sam’s, etc.

Remember to prepare your state return as well—if you live in a state that has a state income tax.

https://ttlc.intuit.com/community/state-taxes/help/how-do-i-contact-my-state-department-of-revenue/0... 

When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s.  Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS/state received the return.

Federal and state returns must be in separate envelopes and they are mailed to different addresses.  Read the mailing instructions that print with your tax return carefully so you mail them to the right addresses.

Note:  The desktop software you need to prepare the prior year return must be installed/downloaded to a full PC or Mac.  It cannot be used on a mobile device.

[KatrinaLO]

Each tax year must be filed separately with the IRS. You cannot combine two years of tax information on one tax form.