If this is a SIMPLE Roth IRA you could use the Roth IRA option in the setup wizard. But, in the end, the various plans work the same way from the perspective of payroll calculations. As long as you have the right annual limit set in the formula, the only difference is the field name that prints on the check stub.

If you really want the field to be named SIMPLE_Roth (or something like that) you can go through the setup wizard for Roth 401k or Roth IRA, then go to Maintain menu > Payroll > Reclassify and Rename Payroll Fields. There you can rename the fields to whatever you want. But if you do, you will also have to go to File menu > Payroll Formulas > User Maintained, find both the employee and employer formulas, and change each reference to the field names. For example, each time you find K401 in the formula, you would change it to SIMPLE_ROTH (or whatever you decided to name the field.) And references to K401_ER would have to be replaced with your new employer field name.

The contribution threshold is lower for a Roth IRA. I would think Sage would squawk if I withheld more. Where is the W-2 Box 12 code in the code, which would need to be changed.

You can change the limits in the formula.

Sorry, just realized I missed part of your question.

The W-2 code is in the Payroll Settings Wizard.

Go to the Maintain menu > Default Information > Payroll Settings.

Select Taxes on the left side of the window, and then Assign Tax Fields.

Click the W-2 Fields button. In the screen that opens, you can assign payroll fields and relevant codes to each box on the W-2.

Sorry, just realized I missed part of your question.

The W-2 code is in the Payroll Settings Wizard.

Go to the Maintain menu > Default Information > Payroll Settings.

Select Taxes on the left side of the window, and then Assign Tax Fields.

Click the W-2 Fields button. In the screen that opens, you can assign payroll fields and relevant codes to each box on the W-2.