For the first time, half of private-sector workers are saving in 401(k)s, and it appears people are taking full advantage of it – by becoming millionaires.

Fidelity reported they have 654,000 customers that have over 1 million dollars in a 401k at the end of 2025, the highest level in records going back to the early 2000s. Around 3.2% of more than three million accounts tracked by benefits provider Alight had balances above $1 million as of the third quarter, double the figure at the end of 2022. At T. Rowe Price, roughly 2.6% of participants had balances above $1 million, up from 1.3% at the end of 2022.