With employee contributions of $30,500, an employer contribution would require something in excess of $234,000 of net profit from self employment.
I have not seen any guidance from the IRS regarding how to report Roth employer contributions. For employer contributions to non-owner employees the contribution is to be reported as a traditional 401(k) employer contribution on the W-2 and the employer must issue a Form 1099-R with code G indicating as if there was then an In-plan Roth Rollover with the gross and taxable amounts both being equal to the amount of the employer Roth contribution. Applying this same method to a self-employed employer Roth 401(k) contribution, you would enter it as a traditional employer contribution an then issue to yourself the aforementioned code-G From 1099-R (probably entered as a substitute Form 1099-R (Form 4852) so that explanation could be provided, but including Form 4852 will prevent you from being able to e-file.) I don't know if this is what the IRS expects, but it produces the correct result.
