Can I use 2022 SSN for 2021 income tax return?

yes, use the SS# to file in 2021.  Sounds like she is a resident alien (marriage visa), so the way to get the benefit of that is to use the SS#.  The fact that the SS# was not provided until 2022 is immaterial to the equation.

https://www.irs.gov/forms-pubs/using-a-social-security-number-ssn-or-individual-taxpayer-identification-number-itin-when-filing-your-tax-return

Yes, if she has an SSN issued, use it on your tax return.

However, you won't be able to e-file.

If your wife previously used an ITIN, she will also need to send a letter to the IRS reporting the change.  This is separate from the tax return (different address, different envelope). 

https://www.irs.gov/individuals/additional-itin-information

The fact that an SSN was issued in 2022 might affect her eligibility for certain credits on the 2021 tax return, but let the IRS figure that out.  You may not actually be affected, depending on your tax facts. 

spam

Is this information still correct?  Is there a document, rule, statue, regulation, etc. confirming what you posted?  Thanks.