Retirees face two persistent problems: matching steady cash needs with uncertain markets and managing taxes across account types as rules change. This guide walks you, step by step, through building a three-tier retirement income "waterfall" that coordinates pension payments, Social Security, 401(k) and traditional IRA withdrawals, Roth IRAs, and required minimum distributions (RMDs). The approach is practical—you’ll learn how to cover essential spending, fund discretionary lifestyle goals, and preserve a legacy—while keeping taxes and RMD timing in view.

Why a three-tier waterfall?

Rather than treating all accounts the same, the three-tier model aligns account tax treatment with spending priorities. It helps you:

  • Ensure essential expenses are covered predictably (housing, healthcare, basic living).
  • Support flexible lifestyle spending (travel, hobbies) while controlling tax exposure.
  • Preserve tax-efficient assets (Roth) for legacy or late-life needs, including large medical costs or long-term care.

Overview of account roles

Before building the waterfall, confirm each account’s tax and distribution rules:

  • Pension: Usually pays a monthly annuity; predictable and often indexed. Check survivor options and whether a lump-sum buyout is available.
  • Social Security: A lifetime inflation-adjusted benefit. Claiming age affects benefit size and interacts with other income and taxes.
  • 401(k) and traditional IRA: Tax-deferred; withdrawals are taxed as ordinary income. Subject to RMDs beginning at age 73 (2026 rules for most beneficiaries).
  • Roth IRA: Contributions and qualified withdrawals are tax-free; Roth IRAs are not subject to lifetime RMDs for the original owner.

Step 1 — Quantify your essential spending and safety floor

Start by separating must-cover expenses (housing, utilities, insurance, Medicare premiums, food, property tax) from discretionary spending.

  1. List guaranteed income streams: pension and expected Social Security. Sum monthly totals.
  2. Subtract pensions + Social Security from monthly essentials. The gap is your essential cash shortfall.
  3. If the gap is zero or negative, your safety floor is secure—use higher tiers for flexibility. If positive, you need predictable withdrawals to fill it.

Example: A retiree with a $9,000 annual pension and planned Social Security of $12,000/year has $21,000 in guaranteed income. If essentials run $30,000, the gap is $9,000 annually.

Step 2 — Inventory accounts and tax buckets

Create a one-page account map listing balances and tax status:

  • Taxable brokerage: balance, cost basis (capital gains treatment).
  • 401(k) / Traditional IRA: balances and whether any are employer plans with in-service withdrawal rules.
  • Roth IRA: balance and conversion history (if applicable).
  • Pension specifics: survivor option, cost-of-living adjustment, or lump-sum value.

Knowing the mix helps determine which accounts should fund each tier and whether Roth conversions or rollovers make sense.

Step 3 — Allocate accounts to tiers

Assign account sources to the three tiers. These are guiding principles, not iron rules.

  • Tier 1 — Essential (first-dollar safety): Use guaranteed income first—pension and Social Security. If a shortfall remains, add highly predictable sources: annuity payments (if already purchased), short-duration bond ladders, or systematic withdrawals from a 401(k)/IRA sized to cover this need.
  • Tier 2 — Lifestyle (tax-aware flexibility): Fund discretionary spending from accounts in a tax-efficient order tuned to your tax-bracket goals. Common approach: taxable accounts first (to take advantage of lower long-term capital gains rates and preserve tax-advantaged accounts), then tax-deferred 401(k)/IRA withdrawals, and selectively Roth withdrawals to manage tax brackets.
  • Tier 3 — Legacy / Contingency: Preserve Roth IRAs and remaining tax-advantaged capital for heirs or late-life needs. Because Roth IRAs grow tax-free and aren’t subject to lifetime RMDs, they are ideal for this tier.

Step 4 — Build the withdrawal sequence with rules

Design a repeatable sequence that you can trust and adjust each year. A widely used, tax-conscious starting point:

  1. Use pension + Social Security first for essentials (Tier 1).
  2. Tap taxable accounts for discretionary needs to take advantage of capital gains rates and to keep ordinary income low.
  3. Withdraw from 401(k)/traditional IRAs next, mindful of current-year tax bracket and future RMD consequences.
  4. Withdraw Roth IRA funds last to preserve their tax-free growth—unless you’re intentionally doing Roth conversions to manage future RMDs.

That order can change based on individual factors: a low-income year can be an opportune time for partial Roth conversions (taxable now, tax-free later), while high-Medicare-income years merit caution because of IRMAA surcharges.

Step 5 — Integrate RMDs and the 73 rule

Required minimum distributions from traditional IRAs and employer plans generally begin at age 73 for people who turned 72 after 2022. Plan ahead:

  • Estimate RMDs for years approaching age 73. Use the IRS distribution tables and year-end balances to model the impact on taxable income.
  • Consider whether partial Roth conversions in the early 70s—when tax brackets remain manageable—can reduce taxable balances that drive future RMDs. Conversions are taxable in the conversion year and must be weighed against current rates and future RMD exposure.
  • Remember Roth IRAs owned by the original owner are not subject to lifetime RMDs—tactical preservation of Roths can reduce mandatory taxable withdrawals later.

Practical example — Putting numbers to the plan

Scenario: Single retiree, age 66 in 2026

  • Pension: $9,000/year
  • Expected Social Security at FRA (67): $18,000/year
  • Savings: $450,000 traditional 401(k)/IRA, $80,000 taxable brokerage, $60,000 Roth IRA
  • Essentials: $30,000/year; Lifestyle: $15,000/year

Stepwise execution:

  1. Tier 1: Pension + Social Security (once started) cover $27,000—after claiming SS at FRA the gap shrinks to $3,000 for essentials. Before claiming, pension alone leaves a $21,000 gap that must be sourced.
  2. Prior to claiming SS (age 66–67): use taxable brokerage to cover essentials and some lifestyle. This leverages capital gains treatment and delays larger taxable withdrawals from the 401(k).
  3. After age 67 and once Social Security begins, reduce taxable withdrawals and cover lifestyle spending with a mix: taxable account until depleted, then modest IRA withdrawals calibrated to stay in the 12–22% tax brackets.
  4. At age 73, model RMDs: a $400,000 IRA might produce an RMD around $15,000 (varies by IRS life expectancy factor), which will be taxed as ordinary income. If this RMD would push you into a higher bracket, consider doing some Roth conversions in your late 60s when taxable income is lower.

Step 6 — Annual review and trigger points

Set calendar triggers for reviews:

  • Each year: re-run cash-flow and tax projection for RMD year impacts.
  • When taxable balance drops below thresholds for your target bracket: consider Roth conversions in years with unusually low taxable income (e.g., retirement transition years, years with capital losses).
  • Before age 73: finalize your plan for RMDs and confirm beneficiaries are up to date on Roth IRAs, IRAs and 401(k)s.

Common pitfalls and how to avoid them

  • Ignoring RMD timing: Waiting until 73 without modeling RMDs can cause forced taxable distributions at inopportune times. Model well before age 73.
  • Using Roths too early: Withdrawing from Roths for lifestyle spending can squander their tax-free growth advantage. Treat Roths as your last resort or legacy asset unless a conversion strategy dictates otherwise.
  • Poor Social Security timing: Claiming too early can permanently reduce lifetime benefits and complicate your waterfall. Run break-even analyses for your health, longevity expectations and tax context.
  • Not coordinating pension survivor options: Electing a single-life pension to increase monthly pay can reduce survivor protection. Map pension choices to household needs before choosing.

When to hire a pro

Work with a fee-only financial planner or CPA if you have any of the following:

  • Large or complex pension lump-sum choices with rollover implications.
  • Multiple IRAs, Roth conversions, or state tax complexities.
  • High taxable investment balances that could trigger Medicare IRMAA or phaseouts.
  • Estate planning that requires coordination of beneficiary designations across account types.

Action checklist — next 90 days

  1. Create a one-page account inventory by tax bucket (taxable, tax-deferred, tax-free) and list balances.
  2. Calculate your essential spending and confirm guaranteed income coverage from pension and Social Security.
  3. Run a simple projection of RMDs at age 73 for each tax-deferred account.
  4. If you have a low-income year coming, model a partial Roth conversion amount that keeps you within your target tax bracket.
  5. Update beneficiaries on all accounts and confirm pension survivor elections align with household needs.

Final considerations

The three-tier waterfall is a rule-based framework that brings clarity to otherwise messy decisions. It preserves tax flexibility, helps smooth spending, and keeps RMDs and Social Security timing in view. In 2026’s higher-rate environment, the principles still hold: lock down essentials with guaranteed income, be tax-aware in discretionary withdrawals, and protect Roth assets for long-term flexibility and legacy goals. Regular modeling—annually and before major milestones like age 73 or a pension election—will keep the plan responsive to market and life changes.

If you follow the steps above, you’ll replace guesswork with a repeatable, tax-conscious routine tailored to your priorities: cover the essentials, enjoy the lifestyle you want, and leave a tax-efficient legacy.