Please refer to our February 26, 2015 blog post for potential legislative developments regarding the ability to convert after-tax contributions to Roth contributions.
Plan sponsors seeking to provide employees with the ability to make after-tax contributions to a 401(k) plan may be interested in adding, along with the common Roth contribution feature, non-Roth after-tax contribution and “in-plan Roth rollover” features to their 401(k) plans. These additional features would allow plan participants to save up to $53,000 (for 2015 and as reduced by matching and other employer contributions) annually with limited future tax liability.