The success of a federal retirement plan hinges on two things. Yes, auto-enrollment is a big factor. But what matters even more is time: Our research shows that the longer workers stay in the system, the greater their gains.

Universal retirement plan access is back at the center of policy conversation after President Donald Trump signed an executive order on April 30. While the order stopped short of creating a federally administered auto-enrollment retirement plan, it aims to address a persistent issue: millions of workers lack a simple, consistent way to save for retirement through their workplace.

In our latest research, we analyzed the impact on retirement wealth if that gap narrowed.

The TakeawaysLower-income workers who would be directly affected by a federal retirement plan experience the largest proportional gains.Automatic enrollment produces more than double the wealth gains of voluntary enrollment at the same contribution rate.Potential enhancements to the Saver’s Match program can amplify gains, especially for lower and middle-income workers.Long-term participation has a larger impact on outcomes than plan design.Which Groups Benefit the Most?

We used the Morningstar Model of US Retirement Outcomes to simulate a scenario where workers without access to an employer-sponsored plan or state auto-IRA are automatically enrolled into a federal retirement plan, structured as a Roth account. We evaluated automatic and voluntary enrollment, plus different default contribution rates and automatic escalation.

We also modeled Saver’s Match enhancements, such as expanded eligibility and higher matching rates, to assess how stronger incentives could influence retirement outcomes across different groups.

But we didn’t stop there. We incorporated real-world behaviors like opt-outs, job changes, and preretirement withdrawals. These can materially affect how much workers ultimately accumulate and help avoid overstating the impact of policy changes.

So who benefited the most? We found that Gen Z workers directly affected by a federal retirement plan could experience retirement wealth increases of up to 62%, compared with 55% for millennials and 33% for Gen X. Under enhanced Saver’s Match scenarios, Gen Z gains exceed 100%.

The table below shows the average percentage change in retirement wealth at age 65 for those three age groups combined under each scenario.

The benefits are concentrated among those with the most to gain. Single women, Gen Z and millennial workers, Hispanic and non-Hispanic Black workers, and lower- and middle-income workers see the largest wealth increases.

When analyzing the impact by income level in our base scenario, we found that workers in the lowest income quartile experienced gains of roughly 36% when auto-enrolled at 3%, compared with an increase of 16% for those in the highest income quartile. Under expanded Saver’s Match eligibility, these gains increase to roughly 108% for the lowest income quartile while remaining about the same for higher-income workers (because they generally do not qualify for the Saver’s Match).

Download the retirement reportThe Importance of Duration

While access and enrollment design influence results, the length of time a worker remains in the system ultimately determines the magnitude of the gains, as shown in the table below.

These results suggest that policies that do not explicitly address persistent participation may be missing the more consequential lever. Features such as portability, re-enrollment mechanisms, and plan continuity across job changes may matter just as much as the initial act of enrolling workers in the first place.

Adding Billions in Wealth to the System

We estimate that approximately 32.3 million workers would enter the retirement savings system over time under a federal auto-enrollment plan, even accounting for opt-outs.

Under the base scenarios, the federal retirement plan adds between $635 billion and $983 billion in estimated wealth to the system over 10 years, rising to between $981 billion and $1.35 trillion when combined with enhancements to the Saver’s Match. By comparison, under the voluntary enrollment design in the base scenario, the increase is substantially smaller, at approximately $283 billion, reflecting lower participation and contribution rates.

The implication of our research is straightforward: Expanding access is a starting point, not a solution. The effectiveness of a federal plan will depend on whether it increases participation and keeps workers consistently saving over time.