How does Social Security fit into a FIRE plan you start in your 40s?

Social Security still matters for early retirees — it's essentially inflation-protected longevity insurance that kicks in later, reducing how much your portfolio must carry in your 70s, 80s, and beyond. Your benefit is based on your highest 35 years of earnings, so retiring early with fewer than 35 working years means some zero-income years drag the average down, though the progressive formula softens the hit. Claiming can start at 62, but waiting until 70 grows the benefit by roughly 8% per year past full retirement age, which many FIRE'd retirees do because it's a strong guaranteed return and a hedge against outliving savings. Some intentionally run Roth conversions in their low-income early-retirement years, before Social Security pushes income up. Don't assume zero — even a reduced benefit meaningfully lowers your required nest egg. Estimate claiming strategies at wealthserene.com/tools/social-security-optimizer.