With no W-2 income, because a Roth contribution of $600 requires having net profit from self-employment of more than $600 and net profit of more than $600 requires filing a tax return, a Roth contribution of $600 (which will be reported by the custodian to the IRS on a Form 5498) with no tax return filed implies that either the Roth contribution is an excess contribution or that the individual has under-reported self-employment income that is subject to self-employment taxes.
