401(k) and Social Security Guide: Maximize Your Retirement

How 401(k) and Social Security work together

Your 401(k) offers:

• Personal savings growth potential
• Tax advantages during working years
• Flexible withdrawal strategies
• Higher contribution limits ($24,500 base limit in 2026)

The key difference? Social Security replaces about 40% of your pre-retirement income. Your 401(k) helps bridge the gap to maintain your lifestyle.

Social Security benefits explained

Social Security looks at your best 35 working years to calculate your benefit amount. If you earn $60,000 and contribute $6,000 to your 401(k), you pay income tax on $54,000. But Social Security still counts the full $60,000 toward your future benefits.

This means maxing out your 401(k) actually helps you twice. You save on current taxes AND keep your Social Security benefits intact.

401(k) account advantages

Your 401(k) plan gives you control over when and how much you withdraw. Unlike Social Security, which provides fixed monthly payments, you can adjust your 401(k) withdrawals based on your needs and tax situation each year.

Do 401(k) contributions reduce Social Security benefits?

No. Your 401(k) contributions come out of your paycheck before you pay income taxes. This means you save money on taxes. But Social Security still counts these earnings. Your full earnings stay on your Social Security record.

When 401(k) withdrawals trigger Social Security taxes

Here's where it gets tricky. While 401(k) contributions don't hurt your Social Security benefits, withdrawals can trigger taxes on those benefits through something called "provisional income."

The provisional income formula:

• Your regular income
• Plus tax-exempt interest
• Plus 50% of your Social Security benefits

2026 tax thresholds:

• Single filers: Benefits become taxable above $25,000 provisional income
• Married filing jointly: Taxable above $32,000 provisional income
• Higher thresholds: $34,000 (single) and $44,000 (joint) trigger taxation on up to 85% of benefits

Real-world example: You receive $20,000 in Social Security and withdraw $25,000 from your 401(k). Your provisional income equals $35,000 ($25,000 + $10,000). Since this exceeds $34,000, roughly $5,350 of your Social Security becomes taxable.

The provisional income tax trap

Many retirees are shocked to discover that their Social Security benefits are taxable. Here's why: A $20,000 401(k) withdrawal that seems modest can push your provisional income high enough to tax 50-85% of your Social Security benefits.

This invisible "tax increase" can cost thousands annually. That's why strategic withdrawal planning is essential in order to prevent your different income sources from working against each other.

Calculate your provisional income

How to calculate your provisional income (4 simple steps)

Step 1: Add up all your income sources

Start with your regular income. This includes 401(k) withdrawals, IRA withdrawals, wages, pensions and any other income. Write down the total.

Example: $25,000 (401(k) withdrawal) + $8,000 (part-time work) = $33,000

Step 2: Add tax-exempt interest

If you own municipal bonds or other tax-exempt investments, include that interest amount.

Example: $33,000 + $1,500 (municipal bond interest) = $34,500

Step 3: Add 50% of your Social Security

Take your total Social Security benefits for the year and multiply by 0.5 (50%).

Example: $34,500 + $10,000 (50% of $20,000 Social Security) = $44,500

Step 4: Compare to the threshold

• Single filers: Compare to $25,000
• Married filing jointly: Compare to $32,000
• If you exceed these, your Social Security becomes taxable

Example: $44,500 exceeds the single threshold ($25,000), so you'll owe taxes on some Social Security benefits.

5 smart withdrawal strategies to minimize taxes

You can control how much tax you pay on Social Security by managing your withdrawal timing and sources.

Strategy 1: Delay Social Security claims

Retiring early? Consider living off 401(k) funds while delaying Social Security until age 67 or 70. This approach offers two benefits:

• Your Social Security payments grow by 8% each year you delay (until age 70)
• You avoid the provisional income tax trap during early retirement years

Strategy 2: Mix Roth and traditional withdrawals

Roth and 401(k) withdrawals don't count toward provisional income. By mixing withdrawal sources, you can stay below tax thresholds.

Smart approach: Withdraw from traditional 401(k) accounts up to the provisional income limit, then switch to Roth withdrawals for additional needs.

Strategy 3: Time Roth conversions

Move money from a traditional 401(k) to a Roth account during years when you earn less income. The money you move grows without taxes, and you never pay taxes when you take it out later.

Best timing: Convert during the years between retirement and Social Security claiming, when your income might be lower.

Strategy 4: Geographic tax planning

Consider your state's tax treatment. In 2026, 41 states and Washington, D.C., don't tax Social Security benefits at all. If you're flexible about where you retire, this could save thousands annually.

Strategy 5: Charitable distribution planning

If you're charitably inclined, qualified charitable distributions (QCDs) let you donate up to $111,000 directly from your IRA to charity in 2026. These distributions count toward your RMD but don't increase your adjusted gross income.

401(k) withdrawal strategies compared

Complete retirement income planning guide

Your retirement likely includes more than just Social Security and 401(k) funds. Here's how different income sources work together:

Traditional pensions

• Provide guaranteed monthly payments
• Count toward provisional income for Social Security taxation
• Offer stability but less flexibility than 401(k) accounts

Individual retirement accounts (IRAs)

• Follow similar rules to 401(k) accounts
• Traditional IRA withdrawals count toward provisional income
• Roth accounts offer tax-free withdrawals that remain tax-free and don't affect Social Security

Personal savings and investments

• Taxable investment withdrawals count toward provisional income
• Municipal bond interest doesn't trigger current taxes, but affects Social Security taxation
• Capital gains from asset sales increase your taxable income

2026 retirement rule changes you must know

Several rule changes take effect in 2026 that impact your retirement planning.

5 Major 2026 retirement rule changes

1. Higher 401(k) contribution limits give you more tax-free savings.

• Base limit: $24,500 (up from previous years)
• Age 50+ catch-up: Additional $8,000 (total: $32,500)
• Ages 60-63 super catch-up: Additional $11,250 (highest earners only)

Why this matters: Increased limits help you build retirement savings faster

2. New Roth requirements for high earners change how you save.

• If you earned over $150,000 in 2025, catch-up contributions must go to Roth accounts only
• You pay taxes now, but withdraw tax-free later

Why this matters: Reduces high-income earners' ability to defer taxes

3. Later RMD ages give you more control over when you withdraw.

• Born 1951-1959: RMDs start at age 73
• Born 1960 and later: RMDs start at age 75
• Roth 401(k) accounts: No RMD requirement during your lifetime

Why this matters: More flexibility to manage retirement income and taxes

4. Lower RMD penalties reduce the cost of mistakes.

• Missed RMD penalty: 25% (down from 50%)
• Fix it within two years: Penalty drops to 10%

Why this matters: It makes it less financially devastating if you forget

5. Social Security increases provide modest inflation relief.

• COLA increase: 2.8% for 2026
• Wage base for taxation: Up to $184,500
• Medicare Part B: $202.90/month

Why this matters: Your benefits increase with inflation, but so do your Medicare costs

Tax benefits for seniors in 2026

A temporary senior bonus deduction runs through 2028, offering additional tax relief:

• Single filers age 65+: Extra $6,000 deduction
• Married couples (both 65+): Extra $12,000 deduction
• Income limits apply: Phase-out begins at higher income levels

Advanced tax-smart retirement strategies

Qualified Charitable Distributions (QCDs)

If you're charitably inclined, QCDs let you donate up to $111,000 directly from your IRA to charity in 2026. These distributions count toward your RMD but don't increase your adjusted gross income.

Geographic tax planning

Consider your state's tax treatment. In 2026, 41 states don't tax Social Security benefits at all. If you're flexible about where you retire, this could save thousands annually.

Medicare considerations

High retirement income triggers Medicare surcharges. In 2026, single filers earning over $109,000 or couples earning over $218,000 pay higher Part B and Part D premiums. Strategic timing of withdrawal can help you avoid these thresholds.

401(k) withdrawal rules and timing

You have several options for accessing 401(k) funds:

Age 55 rule

Did you leave your job at age 55 or older? If yes, you can take money from that 401(k) without paying the 10% penalty.

Standard age: 59½

Reach 59½, and you can withdraw from any 401(k) without penalties, regardless of employment status.

Required withdrawals

You must begin taking required minimum distributions at age 73 or 75 (depending on your birth year). The IRS provides tables showing exactly how much you must withdraw each year.

Social Security disability and 401(k) planning

If you receive Social Security Disability Insurance, your 401(k) withdrawals won't affect your SSDI eligibility or payment amount. However, those withdrawals increase your taxable income, potentially making your SSDI benefits subject to tax using the same provisional income rules.

Plan the timing of your withdrawal carefully if you're transitioning from SSDI to regular Social Security retirement benefits.

How withdrawal strategy changes with income level

SCENARIO 1: Single Retiree, Moderate Income

• Age: 66, retired at 62
• 401(k) balance: $250,000
• Social Security (full retirement age): $22,000/year
• Strategy: Withdraw $15,000/year from traditional 401(k) + $22,000 Social Security = $37,000 provisional income. Tax result: 50% of Social Security becomes taxable.
• Better strategy: Withdraw $8,000 from traditional 401(k) + $8,000 from Roth IRA + $22,000 Social Security = $30,000 provisional income. Tax result: Only 35% of Social Security becomes taxable. Annual tax savings: approximately $1,200

SCENARIO 2: Married Couple, Higher Income

• Ages: 68 and 66
• 401(k) balance: $600,000
• Combined Social Security: $44,000/year
• Pension income: $25,000/year
• Total provisional income: $69,000 (well above the $44,000 threshold)
• Strategy: Use Roth conversions during earlier retirement years to shift income and reduce provisional income during high-income years. Potential tax savings: $3,500-$5,000 annually

SCENARIO 3: Single Retiree, Early Retirement

• Age: 58, retired at 55
• 401(k) balance: $400,000
• No Social Security claimed yet
• Strategy: Withdraw $35,000/year from 401(k) (Rule of 55 allows penalty-free withdrawals). Delay Social Security until 70 for 24% higher payments. Result: Lower provisional income during early retirement + 24% larger Social Security at age 70

Your 2026 retirement planning checklist

Use this checklist to ensure you're optimizing your 401(k) and Social Security strategy:

Income & projection planning

☐ Calculate your expected Social Security benefit (visit ssa.gov)

☐ Determine your provisional income based on all retirement sources

☐ Identify which years you'll claim Social Security

☐ Review your 401(k) balance and distribution timeline

Tax strategy

☐ Determine if traditional or Roth 401(k) contributions make sense for your tax bracket

☐ Explore Roth conversion opportunities during low-income years

☐ Review whether you qualify for qualified charitable distributions (QCDs)

☐ Check if geographic relocation could reduce state income taxes on retirement income

2026 specific actions

☐ Confirm your 401(k) contribution limits ($24,500 base or $32,500 with catch-up)

☐ If you're age 60-63 and earned over $150,000 in 2025, plan for new Roth catch-up rules

☐ Review Medicare Part B premium changes ($202.90 for 2026)

☐ Note your RMD age (73 or 75, depending on birth year)

Account management

☐ Review all 401(k), IRA, and Roth account balances

☐ Update beneficiary designations on all retirement accounts

☐ Check if you qualify for the senior bonus deduction (extra $6,000-$12,000)

☐ Schedule a consultation with a financial professional about your specific situation

Create your personal retirement strategy

Every situation is unique. Consider these factors when developing your approach:

Your health and longevity expectations influence whether delaying Social Security makes sense. If you expect to live well into your 80s or 90s, the 8% annual growth for delayed claiming becomes very valuable.

Your current tax bracket vs. expected retirement bracket determines whether traditional or Roth contributions make more sense now.

Your other income sources affect how aggressively you need to manage the Social Security taxation thresholds.

Your legacy goals influence whether you should minimize withdrawals from tax-advantaged accounts or spend them down first.

Take action on your retirement planning

Understanding how your 401(k) and Social Security work together gives you power over your financial future. The strategies in this guide can help you keep more of your hard-earned money and create a reliable retirement income.

But general strategies need personal application. Your specific situation – income levels, family circumstances, health considerations, and financial goals – all influence which approaches work best for you.

Ready to create your personalized retirement strategy? Our experienced financial professionals understand these complex interactions and can help you optimize your specific situation. They'll analyze your complete financial picture and recommend strategies tailored to your needs.

Find your local Associated Bank team today and take the first step toward a more secure retirement. Your future self will thank you for the planning you do today.