What Do Retirement Income Planners Say Is the Costliest Sequencing Mistake Retirees Make?
The order retirement decisions get made in can matter almost as much as the decisions themselves.
The short answer
Much of the general planning discussion around this points to one recurring theme: withdrawing from tax-advantaged accounts in the wrong order, especially when combined with claiming Social Security too early out of habit rather than analysis, tends to be the most cited costly sequencing mistake. The common thread across these discussions isn’t any single decision but treating retirement income sources as if they can be decided independently of each other.
Why sequencing gets treated as its own topic
Retirement income doesn’t come from one place — it typically comes from some mix of savings withdrawals, Social Security, and sometimes a pension, each with its own tax treatment and timing flexibility. A downturn early in retirement can be more damaging than the same downturn later, a dynamic known as sequence of returns risk, which is one reason the order withdrawals happen in gets so much attention separately from the withdrawal amount itself.
The withdrawal-order mistake
One frequently cited pattern is withdrawing from accounts without much regard for how each withdrawal is taxed, rather than coordinating across account types. Spending down one type of account first without considering how it interacts with future required distributions or future tax brackets can create a larger tax burden later that a more deliberate order might have avoided. This is closely related to the general idea of using a safe withdrawal rate as a starting point, but withdrawal amount and withdrawal order are two different levers.
The Social Security timing mistake
A second commonly cited pattern is claiming Social Security at the earliest available age purely out of habit or short-term cash need, without weighing how that timing interacts with other income sources. Benefits calculated relative to full retirement age change based on when they’re claimed, and claiming early locks in that adjustment for the life of the benefit. Planners often point out that the decision looks very different in isolation than it does once considered alongside withdrawal strategy from other accounts, since the two decisions affect the same household budget.
Why these mistakes compound each other
The costliest version of this isn’t usually one bad decision — it’s several individually reasonable decisions made in the wrong order without seeing how they interact. Drawing heavily from one account type while also claiming benefits early, without checking how the two decisions read together, tends to be what gets emphasized in these planning conversations more than a single dramatic misstep. Coordinating retirement withdrawal changes after a market downturn with the broader sequencing picture is one example of how these pieces are meant to be reviewed together rather than in isolation.
What to weigh
None of this points to one universal right order, since the ideal sequence depends on account mix, tax situation, health, and other personal factors that differ by household. What the general planning consensus does point to consistently is the value of mapping out withdrawal and claiming decisions together, ahead of time, rather than making each one reactively as it comes up.