Worked Example: Calculate Net Pay With 401(k), Health Insurance, and Garnishments

Calculating take-home pay gets complicated once you add 401(k) contributions, health insurance, HSA, and especially a wage garnishment. This walkthrough shows every deduction step-by-step using the payroll deduction calculator.

The Scenario

James earns $72,000 annual salary paid semi-monthly (24 paychecks per year). He contributes 6% to his 401(k), pays $180/month for health insurance, $300/month for HSA, and has a 15% wage garnishment for unpaid taxes. Federal withholding is 14% and state tax is 5%. FICA applies at 7.65%.

Step 1: Calculate Gross Pay Per Paycheck

James is paid semi-monthly, so he gets 24 paychecks per year:

$72,000 / 24 = $3,000 gross per paycheck

$72,000 / 12 = $6,000 gross per month (for monthly deductions)

Step 2: Calculate Pre-Tax Deductions

401(k) Contribution

401(k) is a pre-tax deduction — it reduces taxable income for federal and state tax (but NOT for FICA):

$3,000 × 6% = $180 per paycheck (401k)

Annual 401(k) contribution: $180 × 24 = $4,320/year

Health Insurance Premium

Health insurance is also pre-tax for federal and state (but not FICA in most cases):

$180/month ÷ 2 paychecks = $90 per paycheck (health insurance)

HSA Contribution

HSA is pre-tax for federal, state, AND FICA:

$300/month ÷ 2 paychecks = $150 per paycheck (HSA)

Total Pre-Tax Deductions

$180 (401k) + $90 (health) + $150 (HSA) = $420 pre-tax deductions per paycheck

Step 3: Calculate Taxable Income

For federal and state tax, subtract 401(k), health, and HSA:

$3,000 − $420 = $2,580 taxable income (federal & state)

For FICA, only HSA reduces the taxable base (401k and health insurance are still subject to FICA in most cases):

$3,000 − $150 = $2,850 taxable income (FICA)

Step 4: Calculate Each Tax

Tax	Rate	Taxable Base	Tax Per Paycheck
Federal income tax	14%	$2,580	$361.20
State income tax	5%	$2,580	$129.00
FICA (Social Security + Medicare)	7.65%	$2,850	$217.96
Total taxes			$708.16

Step 5: Calculate Post-Tax Garnishment

Wage garnishments for unpaid taxes are typically calculated as a percentage of disposable income (gross minus legally-required deductions like taxes and FICA). James's garnishment is 15% of disposable income:

Disposable income = $3,000 − $708.16 (taxes) = $2,291.84 Garnishment = $2,291.84 × 15% = $343.78 per paycheck

Note: Federal law (CCPA) caps garnishments at 25% of disposable income for most debts, so James's 15% is within legal limits.

Step 6: Calculate Net Take-Home Pay

Gross pay: $3,000.00 Minus 401(k): −$180.00 Minus health insurance: −$90.00 Minus HSA: −$150.00 Minus federal tax: −$361.20 Minus state tax: −$129.00 Minus FICA: −$217.96 Minus garnishment: −$343.78 = $527.06 net take-home per paycheck

Annual net take-home: $527.06 × 24 = $12,649.44/year

Step 7: Understand Why Take-Home Is So Low

James's gross annual is $72,000 but his net is only $12,649 — that's a 82.4% reduction! Here's why:

$4,320 goes to 401(k) — invested for retirement, not lost
$2,160 goes to health insurance — necessary coverage
$3,600 goes to HSA — triple tax advantage, can be withdrawn
$8,668.80 goes to federal tax — at 14% effective rate
$3,096 goes to state tax — at 5% effective rate
$5,231.04 goes to FICA — Social Security + Medicare
$8,250.72 goes to garnishment — paying off tax debt

Try It Yourself

Enter James's numbers into the payroll deduction calculator:

Salary: $72,000 (or $3,000 semi-monthly)
401(k) %: 6
Health insurance: $90/paycheck
HSA: $150/paycheck
Federal tax %: 14
State tax %: 5
Garnishment: 15% of disposable

You should see $527.06 per paycheck net take-home.

Key Takeaways

Pre-tax deductions reduce taxes — James saves $58.80/paycheck in federal tax alone from his 401(k) contribution
Garnishments are devastating — 15% of disposable income is $343.78/paycheck or $8,250/year
HSA has triple tax advantage — pre-tax for federal, state, AND FICA (unlike 401k)
Total deductions exceeded gross income share — James keeps only 17.6% of his gross

Related Calculators

Payroll Deduction Calculator — full deduction breakdown
After-Tax Income Calculator — state-by-state comparison
Hourly Paycheck Calculator — hourly version
Salary Tax Calculator — annual salary version
FICA Tax Calculator — Social Security + Medicare breakdown

The Scenario

Step 1: Calculate Gross Pay Per Paycheck

James is paid semi-monthly, so he gets 24 paychecks per year:

$72,000 / 24 = $3,000 gross per paycheck

$72,000 / 12 = $6,000 gross per month (for monthly deductions)

Step 2: Calculate Pre-Tax Deductions

401(k) Contribution

401(k) is a pre-tax deduction — it reduces taxable income for federal and state tax (but NOT for FICA):

$3,000 × 6% = $180 per paycheck (401k)

Annual 401(k) contribution: $180 × 24 = $4,320/year

Health Insurance Premium

Health insurance is also pre-tax for federal and state (but not FICA in most cases):

$180/month ÷ 2 paychecks = $90 per paycheck (health insurance)

HSA Contribution

HSA is pre-tax for federal, state, AND FICA:

$300/month ÷ 2 paychecks = $150 per paycheck (HSA)

Total Pre-Tax Deductions

$180 (401k) + $90 (health) + $150 (HSA) = $420 pre-tax deductions per paycheck

Step 3: Calculate Taxable Income

For federal and state tax, subtract 401(k), health, and HSA:

$3,000 − $420 = $2,580 taxable income (federal & state)

For FICA, only HSA reduces the taxable base (401k and health insurance are still subject to FICA in most cases):

$3,000 − $150 = $2,850 taxable income (FICA)

Step 4: Calculate Each Tax

Tax	Rate	Taxable Base	Tax Per Paycheck
Federal income tax	14%	$2,580	$361.20
State income tax	5%	$2,580	$129.00
FICA (Social Security + Medicare)	7.65%	$2,850	$217.96
Total taxes			$708.16

Step 5: Calculate Post-Tax Garnishment

Disposable income = $3,000 − $708.16 (taxes) = $2,291.84 Garnishment = $2,291.84 × 15% = $343.78 per paycheck

Note: Federal law (CCPA) caps garnishments at 25% of disposable income for most debts, so James's 15% is within legal limits.

Step 6: Calculate Net Take-Home Pay

Gross pay: $3,000.00 Minus 401(k): −$180.00 Minus health insurance: −$90.00 Minus HSA: −$150.00 Minus federal tax: −$361.20 Minus state tax: −$129.00 Minus FICA: −$217.96 Minus garnishment: −$343.78 = $527.06 net take-home per paycheck

Annual net take-home: $527.06 × 24 = $12,649.44/year

Step 7: Understand Why Take-Home Is So Low

James's gross annual is $72,000 but his net is only $12,649 — that's a 82.4% reduction! Here's why:

$4,320 goes to 401(k) — invested for retirement, not lost
$2,160 goes to health insurance — necessary coverage
$3,600 goes to HSA — triple tax advantage, can be withdrawn
$8,668.80 goes to federal tax — at 14% effective rate
$3,096 goes to state tax — at 5% effective rate
$5,231.04 goes to FICA — Social Security + Medicare
$8,250.72 goes to garnishment — paying off tax debt

Try It Yourself

Enter James's numbers into the payroll deduction calculator:

Salary: $72,000 (or $3,000 semi-monthly)
401(k) %: 6
Health insurance: $90/paycheck
HSA: $150/paycheck
Federal tax %: 14
State tax %: 5
Garnishment: 15% of disposable

You should see $527.06 per paycheck net take-home.

Key Takeaways

Pre-tax deductions reduce taxes — James saves $58.80/paycheck in federal tax alone from his 401(k) contribution
Garnishments are devastating — 15% of disposable income is $343.78/paycheck or $8,250/year
HSA has triple tax advantage — pre-tax for federal, state, AND FICA (unlike 401k)
Total deductions exceeded gross income share — James keeps only 17.6% of his gross

Related Calculators

Payroll Deduction Calculator — full deduction breakdown
After-Tax Income Calculator — state-by-state comparison
Hourly Paycheck Calculator — hourly version
Salary Tax Calculator — annual salary version
FICA Tax Calculator — Social Security + Medicare breakdown

The Scenario

Step 1: Calculate Gross Pay Per Paycheck

Step 2: Calculate Pre-Tax Deductions

401(k) Contribution

Health Insurance Premium

HSA Contribution

Total Pre-Tax Deductions

Step 3: Calculate Taxable Income

Step 4: Calculate Each Tax

Step 5: Calculate Post-Tax Garnishment

Step 6: Calculate Net Take-Home Pay

Step 7: Understand Why Take-Home Is So Low

Try It Yourself

Key Takeaways

Related Calculators

About the Author & Editorial Review

Try Our Interactive Business Calculators

Worked Example: Calculate Net Pay With 401(k), Health Insurance, and Garnishments

The Scenario

Step 1: Calculate Gross Pay Per Paycheck

Step 2: Calculate Pre-Tax Deductions

401(k) Contribution

Health Insurance Premium

HSA Contribution

Total Pre-Tax Deductions

Step 3: Calculate Taxable Income

Step 4: Calculate Each Tax

Step 5: Calculate Post-Tax Garnishment

Step 6: Calculate Net Take-Home Pay

Step 7: Understand Why Take-Home Is So Low

Try It Yourself

Key Takeaways

Related Calculators

About the Author & Editorial Review

Try Our Interactive Business Calculators