43% of Americans name not investing earlier as the single biggest financial mistake of their lives, according to a Clarify Capital survey of 1,000 adults. Respondents estimated their net worth would be $40,000 higher today had they started sooner — and one in three put the figure at $100,000 or more. A separate CNBC/MagnifyMoney survey found a nearly identical rate: 45% regret not investing more over the prior decade. On the action side, Bankrate’s nationally representative survey places regret over investment losses or poor investment decisions at roughly 12% — and even that figure captures regret about how one invested, not regret about having started early. The asymmetry is consistent but narrower than the general invest-vs-save entry because this framing isolates timing rather than participation.
The mechanism is compound interest working in reverse as a regret amplifier. A 25-year-old who puts $10,000 into an S&P 500 index fund and leaves it for 30 years at the historical ~10% nominal return ends up with roughly $175,000; the same person waiting until 35 ends up with ~$67,000 — a gap that exists entirely because of the ten lost years, not because of any difference in skill or risk tolerance. Börsch-Supan et al. (2023) confirmed this pattern with peer-reviewed rigor: surveying US adults aged 60-79, they found 58% affirm saving regret — the wish to have saved more earlier. Notably, their analysis found that life shocks (unemployment, health crises, divorce) explained more of the variation than procrastination or psychological traits, suggesting that saving regret is partly driven by circumstance rather than pure inaction bias.
The caveat is regime dependence. These surveys were fielded during or shortly after a 13-year US equity bull run in which the S&P 500 returned roughly 15% annualized. Someone who invested early in Japan’s Nikkei in 1989 waited over 30 years to break even; someone who bought US equities in March 2000 was underwater for a decade. The 43% inaction-regret figure is partly a product of hindsight bias magnified by a historically favorable period. In a high-interest-rate environment — such as 2023-2024, when US savings accounts and CDs offered 5%+ — the gap between “invest early” and “keep in term deposits” narrows considerably. The directional finding (timing regret favors starting early) is robust across most long horizons; the magnitude is era-dependent and should not be read as a universal constant.