3-Bucket Decumulation at $1.5M: 3, 5, and 30-Year Math

The accumulation phase of retirement is governed by a single rule: save more, earn more. The decumulation phase is harder because four problems compound at once. Sequence-of-returns risk means a 30 percent drawdown in year 1 of retirement does more damage than the same drawdown in year 20. Longevity uncertainty means the plan must work whether you live to 78 or 98. Inflation erodes purchasing power at 2 to 3 percent a year, so a $60,000 expense in 2026 becomes a $93,000 expense by 2046. Tax friction from RMDs, IRMAA, and Social Security taxation pushes effective rates higher just as portfolio income peaks. The 3-bucket strategy is one of three serious frameworks (the others being safe-withdrawal-rate dynamic spending and full annuitization) that address all four problems with a single structural decision tree.

This guide builds the bucket allocation for a $1.5 million decumulation portfolio, walks the refill rules, and assigns each bucket to the right account type for tax-location efficiency. The arithmetic is concrete: at a 4 percent withdrawal rate (the Bengen baseline supported by extensive Trinity and Pfau research), the buckets are $180,000, $300,000, and $1.02 million. The structure is not the only valid approach, but it is the one that survives behavioral failure best in real-world drawdowns.

The three buckets defined

Bucket 1: cash, 0 to 3 years of spending

Bucket 1 holds the next 2 to 3 years of withdrawals in cash equivalents. The instruments are high-yield savings accounts (FDIC-insured up to $250,000 per depositor per institution), money market funds (Vanguard Federal Money Market, Fidelity Government Cash Reserves), and short Treasury bills (4-week, 13-week, 26-week, 52-week). The yield in mid-2026 is approximately 4.5 percent on T-bills and 4.3 percent on money market funds. The principal is functionally guaranteed; the only risk is purchasing-power erosion from inflation.

The purpose of Bucket 1 is not yield. It is the buffer that prevents you from selling equities in a drawdown. A 35 percent equity drop in March does nothing to Bucket 1. You continue spending normally. The bear market never enters your monthly budget conversation.

At a $60,000 annual withdrawal, Bucket 1 holds $180,000 (3 years). Some practitioners use 2 years ($120,000) to free more capital for the higher-return buckets. The 3-year size is the safer default because the average peak-to-trough recovery time for the S&P 500 since 1929 is roughly 2 to 3 years on the worst drawdowns. A 3-year buffer means you can survive every historical drawdown without touching equities.

Bucket 2: bonds, years 4 to 8

Bucket 2 holds the next 4 to 7 years of spending in bonds. The instruments are intermediate-term Treasuries (3-year to 10-year, average duration 4 to 6 years), TIPS for inflation protection, short-duration investment-grade corporate bonds, and brokered CD ladders. The yield in mid-2026 is approximately 4.3 percent on 10-year Treasuries and 1.8 percent real yield on 10-year TIPS. Duration matters: shorter-duration bonds have less price volatility when rates move, which preserves Bucket 2's reliability when Bucket 1 needs refilling.

The purpose of Bucket 2 is to refill Bucket 1. Each year that equities perform poorly, Bucket 2 sells some bonds to top up Bucket 1, ensuring the cash buffer never depletes. Bucket 2 also acts as a secondary buffer against equity drawdowns longer than 3 years; combining Buckets 1 and 2, the retiree has 7 to 10 years of spending before any equity must be sold.

At $60,000 annual withdrawals, Bucket 2 holds $300,000 (5 years). The exact size depends on Bucket 1 sizing; together they should cover 7 to 10 years.

Bucket 3: equities, years 9 to 30+

Bucket 3 holds everything beyond year 8 in equities. The instruments are US total stock market funds (VTI, FZROX), international developed (VXUS, FZILX), emerging markets (smaller allocation, 5-10 percent of equity sleeve), and REITs (5-10 percent of equity sleeve). The expected real return is 4 to 6 percent annualized, with annualized volatility of 15 to 18 percent.

The purpose of Bucket 3 is growth. In a 30-year retirement, cash and bonds alone do not generate the real returns required to outlast inflation. Equities solve the longevity problem because their expected real return is materially positive over 20+ year periods. The trade-off: 30 to 50 percent drawdowns happen on roughly a 7 to 10 year cycle.

At $1.5 million total with $480,000 in Buckets 1 and 2, Bucket 3 holds $1.02 million. This is roughly 68 percent of the portfolio in equities, which is higher than most age-based glide paths recommend at 67 (typical: 50 to 60 percent). The bucket structure justifies the higher equity weight because the 7 to 10 year buffer of cash and bonds absorbs the volatility.

Worked example: $1.5M portfolio, age 67, $60K/year spend

Robert and Linda are both 67 and just retired. Their combined Social Security is $42,000/year (each took it at FRA). Their essential and discretionary spending totals $102,000/year. The gap they need to fill from the portfolio: $60,000/year, which becomes the bucket withdrawal target.

Their portfolio:

• Traditional IRA (Robert): $800,000
• Traditional IRA (Linda): $300,000
• Roth IRA (combined): $200,000
• Taxable brokerage: $200,000
• Total: $1,500,000

Bucket assignment

• Bucket 1 ($180,000 cash): $180,000 in the taxable brokerage (money market fund yielding ~4.3 percent). The remaining $20,000 of the taxable brokerage holds Roth-eligible cash for emergency liquidity.
• Bucket 2 ($300,000 bonds): $300,000 in Robert's traditional IRA, allocated to a 5-year Treasury ladder ($60,000 per rung maturing each year for 5 years) plus a TIPS sleeve for inflation protection.
• Bucket 3 ($1,020,000 equities): Spread across all three account types. $200,000 in Roth (all equities for tax-free growth). $200,000 in remaining Robert's traditional IRA (US/international equity index funds). $300,000 in Linda's traditional IRA (US/international equity index funds). $320,000 still needed; that 320 sits in the remaining $0 taxable brokerage after the cash bucket is funded, wait — let me reconcile the arithmetic. Actually with $200,000 in taxable brokerage and $180,000 of that in cash for Bucket 1, only $20,000 remains in taxable. The total available for equities across all accounts: $200K (Roth) + $200K (Robert IRA after $300K bonds) + $300K (Linda IRA) + $20K (taxable) + $300K (Robert IRA, additional equity sleeve) = $1,020K. Net: equities span all four account types proportionally.

Refill rules in operation

Each January, Robert and Linda look at the prior year's S&P 500 total return:

• If S&P returned greater than 10 percent (e.g., 2024): sell $60,000 of equities from the most tax-efficient location and use it to refill Bucket 1. The Treasury ladder rung that matured this year stays in Bucket 2 as a fresh rung at year 5.
• If S&P returned 0 to 10 percent: use the matured Treasury rung from Bucket 2 to refill Bucket 1. Do not touch equities. Add a new 5-year rung to Bucket 2 only if a more favorable yield exists; otherwise let Bucket 2 shrink by one rung this year.
• If S&P returned negative (e.g., 2022): use the matured Treasury rung from Bucket 2 to refill Bucket 1. Do not touch equities. Do not add a new rung to Bucket 2 (let it shrink). After 5 such years, Bucket 2 would be depleted and equity selling becomes unavoidable.

Tax-location refinement

When equities are sold to refill Bucket 1, the order matters:

• First: sell from taxable brokerage, harvesting losses where available and qualifying for long-term capital gains rates (0 percent if combined taxable income stays under $96,700 MFJ in 2026). The 0 percent LTCG bracket is the tax sweet spot for early-retirement years.
• Second: distribute from traditional IRA if the RMD is unmet for the year. Distributions are ordinary income.
• Third: distribute from Roth IRA, only after age 59.5 and 5-year rule satisfied. Roth distributions are tax-free but consume the lowest-tax-cost asset in the portfolio.
• Last resort: distribute from Roth before tax-efficient depletion of other accounts. The Roth is the inheritance asset of choice (no RMDs during the original owner's life, tax-free to non-spouse beneficiaries under the 10-year rule).

The bucket strategy vs alternative decumulation frameworks

Static 60/40 with annual rebalancing

The classic 60/40 portfolio (60 percent equities, 40 percent bonds) rebalances annually to maintain the target allocation. In a bear market, rebalancing forces buying equities (selling bonds). The math works over multi-decade periods, but the behavioral failure rate is high: retirees often abandon the strategy mid-drawdown. The bucket strategy enforces the same general allocation (roughly 68/32 in our example) but converts the rebalance decision into a calendar rule that does not require action during the worst months.

Safe-withdrawal-rate dynamic spending

William Bengen's original 4 percent rule and subsequent research by Pfau and Kitces propose dynamic adjustments to withdrawal rates based on portfolio performance and inflation. Variants include the Guyton-Klinger guardrails (raise spending when the portfolio is up significantly; cut when down materially) and the Blanchett ratchet. These work mathematically but require the retiree to actively model and adjust each year. The bucket strategy handles dynamic adjustment implicitly through the refill rule: in a down year, the retiree does not refill from equities, so equity exposure shrinks slowly as bonds are depleted; in a strong year, equity selling refills both lower buckets.

Full annuitization

Buying a SPIA with the entire portfolio eliminates sequence-of-returns risk entirely (the insurance company bears it), but surrenders all liquidity, all upside, and all estate value. For most retirees with $500K+, a partial annuitization (covering the floor between Social Security and essential expenses) combined with a bucket strategy for the discretionary portion produces better risk-adjusted outcomes than either pure approach.

When the bucket strategy breaks: the failure modes

Extended bear markets exceeding 7 to 8 years

The Japanese stock market from 1990 to 2010 lost 70 percent of value over 20 years. A US retiree in that scenario would deplete Bucket 1 in years 1 to 3 and Bucket 2 in years 4 to 8, then be forced to sell equities in year 9 at deeply depressed prices. US markets have never had this experience post-1929, but a 30-year retirement starting at age 60 has a small but real probability of encountering one. Mitigation: shift more weight to bonds (longer Bucket 2), or include a TIPS sleeve sized to cover essential expenses for 15+ years.

Sustained high inflation

Bucket 1 in cash loses purchasing power 2 to 3 percent per year in normal inflation environments, 5 to 8 percent per year in high-inflation periods like 2022. The 3-year buffer can erode meaningfully if inflation runs 7 percent for 3 consecutive years. Mitigation: hold I-bonds (limited to $10,000/year per person), TIPS in Bucket 2, and bias Bucket 1 toward shorter T-bills that reset to new yields quickly.

Behavioral failure during the first major drawdown

The bucket strategy works only if the retiree actually follows the refill rule. In a 35 percent equity drawdown, the psychological temptation is to sell equities and move to cash. If the retiree does this, they convert a temporary paper loss into a permanent realized loss and abandon the strategy. The behavioral defense is mechanical: write the refill rule down before retirement, share it with a spouse or financial planner, and check the calendar in January for the rebalance decision rather than reading market news.

Implementation checklist for a $1.5M portfolio

• Calculate the bucket sizes: 3 years cash, 5 years bonds, balance in equities. Net out Social Security and any pension income from the withdrawal target first.
• Assign accounts: Cash in taxable. Bonds in traditional IRA. Equities split across Roth, taxable, and remaining traditional IRA balance.
• Build the Treasury ladder: Buy $60,000 of Treasuries maturing each year for 5 years. Use TreasuryDirect for new issues or your brokerage for secondary market.
• Document the refill rule: Write down what triggers a refill from each bucket. Share with your spouse and any financial advisor.
• Schedule the annual review: Pick a date in January each year. Review prior-year equity return, execute the refill rule, do not deviate.
• Coordinate with RMDs: Once RMDs begin at 73, distributions from the traditional IRA bond bucket automatically refill Bucket 1, simplifying the operational flow.
• Re-examine bucket sizes every 5 years: If equity returns have been strong, Bucket 3 may have grown to dominate. Rebalance toward target weights every 5 years.

Key takeaways

• The 3-bucket decumulation strategy holds 3 years of spending in cash, 5 years in bonds, and 25-30+ years in equities, sized to the gap between guaranteed income (Social Security, pension) and total spending.
• For a $1.5M portfolio with a $60K annual withdrawal, the standard bucket sizes are $180K cash, $300K bonds, $1.02M equities. The split assumes net withdrawal after Social Security; smaller buckets if guaranteed income is high.
• The refill rule is the operational core: if equities return more than 10 percent, refill both lower buckets from equities; if 0 to 10 percent, refill Bucket 1 from Bucket 2 only; if negative, do nothing to equities.
• Tax-location matters more than people realize. Cash belongs in taxable accounts; bonds in traditional IRAs; equities split across Roth, taxable, and traditional IRAs with Roth-first priority for equity placement.
• Failure modes: extended bear markets over 7-8 years deplete the buffers and force equity selling at low prices; sustained high inflation erodes Bucket 1 purchasing power; behavioral failure during a 30 percent drawdown causes retirees to abandon the rule.
• The 3-bucket strategy and a static 60/40 portfolio produce similar long-term survival rates in academic studies, but the bucket strategy has lower behavioral failure rates because it converts the bear-market decision into a calendar rule.