Her retirement account hit $300,000 when she was 31 — she says she'll never add another dime. Is this a smart plan?

For many people, saving for retirement is stressful: How much should I be putting away? When will I have enough to retire? Will I have enough, or will I outlive my savings?

So perhaps it's not surprising that a simple retirement formula, called Coast Fi (Coast financial independence), is gaining steam among young people, especially as they face uncertainty around the future of work and concerns about the future of Social Security.

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Jessica Fick is one proponent of this formula. She discovered that, at age 31, she and her husband had $300,000 in savings . They both quit their jobs and haven't added a penny to their investments since 2023, as reported by The Wall Street Journal.

The idea is that they will "coast" on this number from now on, as they believe their retirement account should grow enough by the time they are ready to retire, without them having to make any additional contributions. The belief is that compound interest will do the heavy lifting for them from now on.

Since hitting her own Coast Fi number, Fick and her husband have cofounded The Fioneers , which she describes on LinkedIn as a "voice at the intersection of financial independence and lifestyle design" that offers coaching programs, workshops and retreats.

But Coast FI isn't foolproof, and financial experts warn that it doesn't take into account changing economic and personal circumstances.

"Inflation is the number one killer of retirement success," Jon Zetlmaier, founder of Zetlmaier Wealth Management in Seattle, told The Wall Street Journal.

Many young adults are faced with financial pressures that "are reshaping the timelines — and in some cases the very possibility — of the lives they imagined for themselves," according to Northwestern Mutual's 2026 Planning & Progress Study. That means delaying major milestones, including marriage, homeownership and starting a family.

Nearly three in four (71%) Gen Zers believe they may never be able to afford at least one of these major life milestones. But, as the study points out, they're responding with resilience by "starting to save for retirement years before their parents and grandparents."