Roth not allowed as a catch up

[TPA Bob]

Had a participant in one of our plans say their previous employer would not allow the $5,500 catch up contribution to be Roth. So they could do Roth for 17,500 but the additional 5,500 had to be pretax. I have never heard of this as a feature of a plan. Anyone know why this would be a feature of a Plan?

Thanks.

[Lou S.]

Not only have I never heard of it, I'm not sure it is even allowable under the regulations.

[Kevin C]

I would suspect that either payroll or the recordkeeper can't handle the catch-up properly. While the regs don't directly address Roth deferrals, I think that limitation violates the universal availability requirement. I also doubt that limitation is included in the plan document.