If Roth IRA phases out at single $150k-$165k and joint $236k-$246k, how does the secure act 2.0 allow the contribution to roth if the same issue with income is in place?

[quigley_susan]

How does this work? Does employer automatically convert anything over 23,500, tax year 2025, to Roth if income over 150k or does the employee need to request the change?

[Opus 17]

An employer plan (401k, 403b, etc) is NOT an IRA, and the contribution rules are completely separate.  For 2025, the limit for elective salary deferral (your contribution) to a qualified workplace plan is $23,500, or $31,000 if you are over age 50.  The limit for all qualified plan contributions (employee plus employer) is $70,000.  It does not matter how you split this workplace contribution between pre-tax and after-tax (Roth account). 

Those limits are completely separate from IRA limits.  If you are under the income threshold for a Roth IRA, you can max out out your workplace plan (pre-tax or Roth) AND max out your Roth IRA.  If you are over the income threshold for a Roth IRA contribution, you can still contribute the maximum through your qualified workplace plan. 

[dmertz]

The only thing that the SECURE 2.0 Act did with regard to Roth contributions was require that catchup contributions to employer plans for highly compensated employees be Roth contributions.  As Opus 17 said, this has nothing to do with Roth IRAs or your AGI.  The employer is responsible for enforcing this requirement based on your earnings at that employer by depositing catchup contributions of highly compensated employees into the designated Roth account in the plan (again, not a Roth IRA).

Any contributions to the designated Roth account in your employer plan will be reported as such in box 12 of your W-2 and will not be excluded from the wages reported in box 1.