Quick enduser feedback
Many 401K plans do not allow for 100% deferral because of need for other taxes to be paid by employee such as medicare and social security. Perhaps suggest back to end-users plan redesign limiting IT0169 deferrals to some limit like ~80%
If employee receives $10,000 bonus with 100% deferral I would still expect to see some 401K federal taxable wages for the amounts not deferred to cover ssn/med taxes. Employee cannot defer 100% because other taxes must be paid. This creates kind of reverse grossup.
Sample Math:
| 10,000 | Gross Wages Bonus |
| 8,980 | 401k pretax defferral |
| 1,020 | FED taxable wages |
| 255 | FED TAX @ .25 |
| 620 | SSN TAX @ .62 |
| 145 | MED TAX @ .0145 |
| 1020 | SUBTOTAL TAX |
| 0.00 | NETPAY |
Also will have state taxable wages too. But not all states handle 0169 deferrals the same so not included that part.
Sorry I cannot give technical advice. I am HR/Payroll manager not experience SAP consultant. I would suggest against 100% defferrals for IT0169 plans though.
Good luck.