Can 403b + Roth IRA contributions larger than earned income?

[JasonQSY]

I'm currently a researcher at a public university. The university offered 403b and 457b retirement plans with Roth and traditional options. And I have a Roth IRA account. My question is: Suppose my annual earned income (W-2) is 24,000 (the extreme case). Can I contribute 20,500 to Roth 403b (2022 limit), as well as 6,000 to Roth IRA (2022 limit)?

I understand Roth IRA contribution needs to be after-tax earned income. And Roth 403b is deducted directly from my payroll. I wonder if it's conflicted here. The actual case is I'm not sure if my earned income is sufficient to contribute Roth 403b + Roth 457b + Roth IRA, considering that I'm in pretty low tax bracket right now.

Thank you for your help!

[macuser_22]

If you are a W-2 employee then your taxable compensation for Roth contribution cannot be more then the amount reported in box 1 on your W-2.   Payroll deductions for employer plans are reported on the W-2 box 12 and are not part of box 1.  So no, the income cannot be used twice.