What are the differences between a Roth 401k and an after-tax 401k, and which one would be more beneficial for my retirement savings strategy?

The main difference between a Roth 401k and an after-tax 401k is how they are taxed. Contributions to a Roth 401k are made with after-tax money, meaning withdrawals in retirement are tax-free. Contributions to an after-tax 401k are made with pre-tax money, but withdrawals are taxed as ordinary income. The choice between the two depends on your current tax situation and future retirement goals. If you expect to be in a higher tax bracket in retirement, a Roth 401k may be more beneficial. If you are in a high tax bracket now and expect to be in a lower tax bracket in retirement, an after-tax 401k may be more advantageous.