I think that may be illegal.
[Edited: see @dmertz 's answer for how to report this.]
I know that for any other corporation, non-profit, etc., if the company makes a retirement contribution (matching contribution, free money, etc.) it must be contributed to a pre-tax account, even if the employee has chosen to put their salary deferrals into a Roth-option account in the 401k or 403b plan.
Here, because partnership profits are taxed to the individual partners on a K-1, if you make Roth contributions and don't count them as distributed profits, you have essentially dodged the tax on those profits, which is quite illegal.
There are also important rules about participating in retirement plans if you own the business. I don't know those rules but you need to take them into account.
I think it may be allowable to contribute matching funds to a pre-tax 401k account, because the partner will eventually pay tax on the money when they convert it to a Roth or withdraw it. The 401k plan would be a deductible employment expense. But I think you have a huge problem if you contribute partnership funds to a Roth plan.
@dmertz
@rjs
