The Social Security Optimizer tests every realistic combination of claiming ages against your full plan, runs each one through the Monte Carlo simulation, and ranks the results by plan success rate. The output is a short table that tells you which claiming age (or pair of ages, for couple plans) gives your plan the highest chance of success - and how much you'd gain over your currently configured ages.

Where it lives

The Social Security tab on the Optimizers page. The page also hosts Pension, Spending, and Roth conversion optimizers; each is a separate tab with its own logic. When your plan has both Social Security and a pension with two or more comparable payout options, an SS + Pension tab also appears - it optimizes the claiming age and the pension choice together, since the two decisions interact. See the SS + Pension Optimizer.

What it does

For a single-filer plan, the optimizer runs your plan once per primary claiming age between 62 and 70. For a couple plan, it runs the full grid of primary x spouse claiming ages (62-70 each). Every run is a full Monte Carlo simulation - 2,000 paths through 30+ years - so the comparison is honest: it's measuring how each combination affects success across the same set of return sequences, not just a single deterministic projection.

Two metrics decide the ranking:

• Plan success rate - primary sort key. The percentage of Monte Carlo paths in which your portfolio doesn't run out before the end of the plan.
• Median end balance - shown alongside success rate. Useful as a tiebreaker when two combinations produce similar success rates.

Current settings preview

Before running, the optimizer shows your current SS settings (primary claim age + benefit, spouse claim age + benefit for couples). If you haven't entered SS benefit amounts on the SS & Pension page yet, the optimizer prompts you to fill those in first - no benefit data means the comparison is meaningless.

Reading the results

The results table is sorted by success rate descending. Top row gets a highlight and a "Best" tag. Each row shows:

• Primary Claim Age - the primary's claiming age in that scenario.
• Spouse Claim Age - couple plans only. The spouse's claiming age.
• Success Rate - plan success rate for that claiming combination. The top row also shows the delta vs your current settings, colored green if the optimizer found an improvement and red if your current is better than the optimizer's best (which can happen when "current" is already optimal).
• Median End Balance - the median final portfolio balance, with a delta vs current next to the top row.
• Lowest Balance - the low point of the portfolio's median path, usually in the years before Social Security starts. An amber marker flags rows whose trough falls below 10% of your starting portfolio.
• Apply button - updates your plan's claiming ages to that row's combination. The plan recalculates immediately so the dashboard reflects the new choice.

Why the Lowest Balance column matters

Success rate is a terminal, all-or-nothing measure - it only asks whether the portfolio lasted, not how close it came to empty along the way. A plan that delays Social Security and drains the portfolio to a razor-thin buffer during the bridge years, then coasts on the larger guaranteed benefit, can score a very high success rate while being fragile: there's little cushion left for a bad market or an unexpected expense right when the portfolio is thinnest. The Lowest Balance column surfaces that trough so a high-success-but-nearly-depleted plan is visible instead of hidden behind its headline number. A high success rate with a low trough isn't wrong, but it's a plan leaning hard on guaranteed income - weigh it against a slightly lower-success option that keeps a healthier buffer.

Why claiming age matters

Claiming early (age 62) gives you a permanent benefit reduction; claiming late (age 70) gives a permanent boost of roughly 8% per year past full retirement age. The trade-off isn't obvious because:

• Claiming early means the portfolio carries less of the load in your 60s, leaving more invested through retirement.
• Claiming late means a larger guaranteed lifetime income but more portfolio drawdown in the bridge years.
• The "right" answer depends on your other income sources, expected longevity, market returns, and how aggressively you spend.

For couples, the trade-off includes coordination: the higher earner's claim age also drives the survivor benefit, so a strategy of "lower earner claims early, higher earner claims late" is often (but not always) the right pattern.

Comparing against your current plan

The delta indicators on the top row tell you whether running the optimizer was worth the trip:

• Green delta (e.g. +6% success, +$120k median end balance) - the optimizer found a meaningfully better claiming combination. Worth applying.
• Small delta (within 1-2%) - your current claim ages are already near-optimal. Applying the optimizer's pick is probably a marginal change.
• Negative or zero delta - your current claim ages already are the optimal combination, or close enough to it that the search didn't find improvement.

What this optimizer doesn't do

• Doesn't optimize for survivor income or estate goals directly - the metric is plan success rate, not survivor benefit size or end-of-plan balance. A combination that maximizes one metric may not maximize the others.
• Doesn't model fractional months - claiming ages are whole years. If you're considering claiming at, say, 67 and 4 months, run the optimizer at 67 and 68 and interpolate.
• Doesn't account for SS policy risk - the optimizer assumes the configured COLA holds and benefits aren't cut. If you want to stress-test against an SS cut, use the What-If Explorer's SS cut scenario alongside the optimizer's recommendation.
• Doesn't include spousal benefit timing rules beyond the basic claiming-age coordination. Restricted-application-for-spousal and other strategy options that the law restricts to specific birth cohorts are not modeled.