Until now, you could choose for all of your 401(k) contributions to be made tax-deferred. In other words, they will be treated as Roth 401(k) contributions. Once invested, your after-tax money will be allowed to grow tax free and be withdrawn tax free assuming certain conditions are met. But for those high earners who are affected by the rule change, there are potential upsides and downsides. Plus, thanks to Secure 2.0, unlike with your traditional, tax-deferred 401(k) contributions, you will not be required to make minimum withdrawals from your Roth 401(k) when you turn 73.