Compound Interest After 60: Growth, Fees and Drawdown

Because compounding is a percentage of the balance, and at 60 the balance is at or near its peak. Compound interest is growth earned on earlier growth as well as on the money put in. The rate does not change with age, but the base it applies to does.

A 30-year-old with $50,000 invested at 6% earns about $3,000 in a year. A 60-year-old with $800,000 at the same rate earns about $50,000, which is more than most people save from a salary in the same year. By the late sixties that same portfolio is earning $80,000 or more a year. The contributions have become the small part of the picture.

Worked through: $1,000,000 left for 10 years at 6% compounded annually is $1,000,000 × 1.06¹⁰, or about $1,790,800. Compounded monthly it is about $1,819,400, and daily about $1,822,000. The step from monthly to daily is worth less than 0.2%. Compounding frequency matters for comparing savings accounts and CDs; for a portfolio, the return, the fees and the time the money stays invested decide the outcome.

Simple interest, by contrast, pays only on the original sum. The same $1,000,000 at 6% simple interest for 10 years ends at $1,600,000. The $190,000 difference is interest earned on interest, and it widens every year the money is left alone.

Usually more than the contributions themselves, because most of the gain is growth on the money already saved. Margaret, the hypothetical 60-year-old in the calculator's default example, has $800,000 in a 401(k) and rollover IRA and adds $2,500 a month until she retires at 67. At a steady 6% with monthly compounding:

Of the $676,000 increase, $210,000 is new money and $466,481 is growth. Of that growth, $416,296, about 89%, comes from the $800,000 she started with. In her final working year the portfolio earns nearly three times what she adds.

Two conclusions follow. First, the return and the cost of earning it matter more than the contribution: at 5% she reaches $1,385,250 and at 7% $1,573,993, so one percentage point is worth about $90,000 by 67, three years of contributions. Second, each extra working year is worth more than the one before. Working to 69 on the same terms produces $1,727,809, about $250,000 more for two years, of which only $60,000 is contributions.

Catch-up contributions still add to the base. From 60 through 63, a worker's own 401(k) deferrals can reach $35,750 in 2026, before any employer match; the guide to maximizing a 401(k) covers the rules. Whether two more working years are worth it is a separate question about spending and health, which how much you need to retire works through. Working longer also often means claiming Social Security later, which compounds in its own way: when to claim Social Security covers the delayed credits.

Divide 72 by the annual return to get the years it takes to double: at 6%, $1 million becomes about $2 million in 12 years if nothing is withdrawn. The rule is a shortcut for the exact figure, ln(2) ÷ ln(1 + r), and it is most accurate between about 6% and 10%.

Three practical uses for a retiree:

• Money you will not need for a decade. The share of a portfolio earmarked for your eighties can reasonably be expected to roughly double before you reach it, at the returns a balanced portfolio has historically earned. That is the case for keeping part of a retirement portfolio in stocks.
• Inflation. At 3%, prices double in about 24 years. A couple retiring at 65 should expect their costs to roughly double by 89.
• Reversing it. To double in 10 years you need about 7.2% a year. If a plan depends on a doubling faster than that, the plan is relying on a return that most balanced portfolios have not delivered.

Far more than the percentage suggests, because a fee is taken every year from a balance that would otherwise have compounded. The SEC's own example: $100,000 earning 4% for 20 years grows to about $208,000 with 0.25% in annual expenses and about $179,000 with 1% (SEC Investor Bulletin).

At retirement-sized balances the numbers are larger. $1,000,000 left for 25 years with nothing withdrawn, compounding monthly:

A 1% fee ends up costing 22% of the ending balance. The cost is not visible on any statement, because it is the growth that never happened. Once withdrawals begin the effect is sharper still, as the next section shows, because there are no new contributions to replace what the fee removes.

Yes. The money you have not yet spent keeps compounding, and for a couple retiring in their mid-sixties some of it will stay invested for 25 or 30 years. What changes is the direction of the cash flow and the sensitivity to returns.

Robert and Ellen, a hypothetical couple aged 66, retire with $1,500,000. They take $5,000 a month, 4% of the starting balance, and raise it 3% a year for inflation, so by year 30 they are taking about $11,800 a month. With steady returns and monthly compounding:

At 6% the balance keeps rising until about 91, peaking near $2.08 million, and is still above $2 million at 96. At 5% it peaks around 76 and falls steadily after that. The gap between those two rows at 96, more than $1.2 million, is what a 1% annual fee would cost if it turned a 6% return into 5%. A 0.25% fee, turning 6% into 5.75%, costs about $358,000 by 96.

To run your own version, enter the portfolio as the initial investment in the Compound Interest Calculator, the monthly withdrawal as a negative monthly contribution, and the inflation raise as the annual increase. A rough guide to what can be withdrawn while keeping the real balance intact is the return minus inflation: at 6% and 3% inflation, a first-year withdrawal near 3% of the portfolio. The Retirement Withdrawal Calculator tests rates against a wider range of market outcomes.

Because withdrawals taken after a loss sell shares at low prices, and those shares are not there to compound when markets recover. Before retirement the order of returns does not change the ending balance of a lump sum at all. After retirement it can change it by hundreds of thousands of dollars.

Take ten annual returns that compound to about 5.1% a year: −18%, −8%, 10%, 12%, 9%, 11%, 10%, 8%, 12% and 10%. Apply them to $1,500,000 in that order and in reverse. With nothing withdrawn, both orders end at about $2,469,000; multiplication does not care about order. Now take $60,000 at the start of each year, rising 3% a year:

Same returns, same withdrawals, and a difference of about $354,000 after ten years. The couple who met the losses first also spent eight years with a portfolio smaller than the one they retired with, which is when people abandon a plan.

The defenses are well known and none is free:

• A cash or short-bond reserve of one to three years of withdrawals, so that nothing has to be sold after a decline.
• Flexible spending, such as skipping the inflation raise in a year after the portfolio falls.
• A larger guaranteed floor: delaying Social Security, or taking a pension as an annuity, reduces how much the portfolio has to supply in the early years.
• A lower starting withdrawal rate for the first few years of retirement, when the risk is concentrated.

Retirement withdrawal order covers which accounts to draw from first, which matters to sequence risk because it decides what gets sold.

It compounds against you at its own rate, so the growth that counts is the return after inflation. At 3% a year, a dollar at 65 buys about 55 cents of today's goods at 85 and about 49 cents at 89.

Robert and Ellen's $2.03 million at 96 in the 6% case sounds generous. In the money of their first retirement year, at 3% inflation, it is worth about $838,000, a little over half of what they started with. The plan still worked, because the withdrawals rose with prices the whole way, but the nominal figure overstates the cushion.

Two consequences for planning. First, compare returns net of inflation: a 5% certificate of deposit in a year of 3% inflation compounds purchasing power at about 2%, before tax. Second, assets that tend to keep pace with prices over long periods, such as stocks, Treasury inflation-protected securities and Social Security benefits with their annual cost-of-living adjustment, carry more weight in a 30-year plan than in a 5-year one. The calculator shows nominal dollars; divide by 1.03 raised to the number of years to see a result in today's money at 3% inflation.

The one whose growth will be taxed least when it is finally spent, which for many retirees is a Roth. The same pre-tax balance is worth different amounts depending on where it sits.

• Traditional 401(k) and IRA. Growth is untaxed until withdrawn and then taxed as ordinary income. Required minimum distributions start at 73, or 75 if you were born in 1960 or later, and force part of the balance out each year whether or not you need it.
• Roth IRA and Roth 401(k). Qualified withdrawals are tax-free and the original owner has no required distributions, so a Roth can compound untouched for life and pass to heirs.
• Taxable brokerage. Interest, dividends and realized gains are taxed along the way, which trims the rate at which the account compounds. Unrealized gains held until death generally receive a stepped-up basis, so heirs may owe little on them.

This is why converting some traditional money to Roth in the lower-income years between retiring and the first RMD can leave more of the portfolio compounding tax-free for longer. Roth conversions before RMDs explains the trade-off, and the RMD Calculator shows what a traditional balance will be required to pay out each year.

About three times by college age and more than ten times by 40, at 6%. This is where the long-horizon arithmetic usually quoted to young savers applies to a grandparent: the money is yours, but the time horizon is the grandchild's.

Timing matters more than size: the gift at birth ends up worth nearly twice the same gift at 10. A 529 plan lets a grandparent give five years of annual exclusions at once, $95,000 per grandchild in 2026, by electing to spread the gift over five years on a gift-tax return. That sum left 18 years at 6% would be worth about $279,000. Growth in a 529 is free of federal income tax when spent on qualified education.

Where the money is held affects who controls it later. A custodial account becomes the grandchild's outright at the age set by state law; a 529 stays under the owner's control. The College Savings Calculator covers grandparent-owned 529 plans, and gifting to children and grandchildren covers the gift-tax rules and the choice between giving now and leaving an inheritance.

Historically, investing at once has beaten spreading the money out over several months about two-thirds of the time (Vanguard, 2023), because markets have risen more often than they have fallen and money waiting in cash misses that growth.

The question comes up late in life more than early: a 401(k) rollover, the proceeds of a home sale, an inheritance. Spreading the money in over three to six months is a reasonable compromise if a sharp decline right after investing would lead you to sell. What matters more is the long-run mix of stocks, bonds and cash the money ends up in; asset allocation by age and the dollar-cost averaging guide cover both halves of that decision.