**Net pay formula**: Gross Pay - Pre-Tax Deductions - Tax Withholding - Post-Tax Deductions = Net Pay (take-home). **Step-by-step calculation for 2025**: **Step 1: Start with gross pay**.

Gross pay = salary ÷ pay periods OR hourly rate × hours worked. **Example**: $60,000 annual salary ÷ 26 biweekly periods = $2,307.69 gross per paycheck. **Step 2: Subtract pre-tax deductions** (reduce taxable income).

Common pre-tax deductions: (1) **401(k) contributions**: Up to $23,500 in 2025 ($31,000 if age 50+).

Employee elects contribution % (e.g., 6% of gross). (2) **Health insurance premiums**: Employer-sponsored plan premiums paid by employee. (3) **HSA contributions**: Up to $4,300 individual / $8,550 family in 2025. (4) **FSA contributions**: Up to $3,300 healthcare FSA / $5,000 dependent care FSA in 2025. (5) **Pre-tax commuter benefits**: Up to $325/month for transit/parking in 2025. **Example**: $2,307.69 gross - $138.46 (6% 401k) - $150 (health insurance) = $2,019.23 taxable income. **Step 3: Calculate federal income tax withholding** using **W-4 form** (2020+ version). **W-4 Method**: (1) Determine filing status (Single, Married Filing Jointly, Head of Household). (2) Apply standard deduction: $15,000 single / $30,000 married in 2025. (3) Adjust for Step 2 (multiple jobs) and Step 3 (dependents) claims. (4) Calculate annual taxable income: (Taxable Pay per Period × Pay Periods) - Standard Deduction - Step 3 Amount + Step 4a Amount. (5) Look up tax in **IRS Publication 15-T** tax tables (2025 version). (6) Divide annual tax by pay periods = withholding per paycheck. **2025 federal tax brackets (Single)**: $0-$11,925: 10% | $11,926-$48,475: $1,192.50 + 12% over $11,925 | $48,476-$103,350: $5,578.50 + 22% over $48,475 | $103,351-$197,300: $17,651 + 24% over $103,350 | $197,301-$250,525: $40,099 + 32% over $197,300 | $250,526-$626,350: $57,131 + 35% over $250,525 | $626,351+: $188,770.75 + 37% over $626,350. **Example**: $2,019.23 taxable × 26 periods = $52,500 annual.

Single filer, standard deduction $15,000 → Taxable income $37,500.

Tax = $1,192.50 + (($37,500 - $11,925) × 12%) = $1,192.50 + $3,069 = $4,261.50 annual ÷ 26 = $163.90 per paycheck. **Step 4: Calculate FICA taxes** (7.65% total): (1) **Social Security tax**: 6.2% on wages up to $176,100 wage base in 2025.

Stop withholding once employee earns $176,100 YTD (max tax $10,918.20). (2) **Medicare tax**: 1.45% on all wages (no limit). (3) **Additional Medicare tax**: 0.9% on wages over $200,000 single / $250,000 married (employer withholds once wages exceed threshold). **Example**: $2,019.23 × 7.65% = $154.47 FICA ($125.19 Social Security + $29.28 Medicare). **Step 5: Calculate state income tax withholding** (if applicable). **43 states + DC have income tax** (no tax in AK, FL, NV, NH, SD, TN, TX, WA, WY).

State withholding = based on state W-4 equivalent and tax brackets. **Example (California)**: Use DE 4 form, apply CA tax tables. ~4-6% effective rate for middle income.

Assume $80 state tax per paycheck. **Step 6: Subtract post-tax deductions**: (1) **Roth 401(k)**: Taxed now, grows tax-free (same $23,500 limit as pre-tax). (2) **Garnishments**: Court-ordered wage garnishments (child support, tax levies, creditor judgments).

Up to 25% of disposable income for consumer debt, 50-65% for child support. (3) **After-tax benefits**: Disability insurance, life insurance premiums (if not pre-tax). **Example**: $50 Roth 401(k) contribution. **Step 7: Calculate net pay**. **Full example**: Gross: $2,307.69 | Pre-tax deductions: -$288.46 (401k + health) | **Taxable income: $2,019.23** | Federal tax: -$163.90 | FICA: -$154.47 | State tax: -$80 | Post-tax deductions: -$50 (Roth) | **Net pay: $1,570.86** (**68% take-home rate**). **Verification**: Common take-home percentages by income level: (1) **$30,000-$50,000**: 75-80% (lower tax brackets, fewer deductions). (2) **$50,000-$100,000**: 68-75% (middle brackets, typical benefits). (3) **$100,000-$200,000**: 60-68% (higher brackets, max 401k contributions). (4) **$200,000+**: 50-60% (top brackets + Additional Medicare Tax). **Payroll calculation mistakes to avoid**: (1) **Forgetting to update W-4**: Life changes (marriage, kids, home purchase) can reduce withholding needs. (2) **Mixing pre-tax and post-tax deductions**: Roth 401(k) does NOT reduce taxable income (unlike traditional 401k). (3) **Ignoring state tax**: 43 states have income tax; must withhold for work state (not residence if different). (4) **Social Security wage base**: Stop withholding SS tax once employee hits $176,100 YTD (recalculate take-home mid-year). **Monthly payroll example (salaried employee)**: Annual salary: $75,000 | Pay frequency: Semi-monthly (24 periods) | Gross per paycheck: $75,000 ÷ 24 = $3,125 | Pre-tax 401(k) (8%): $250 | Health insurance: $180 | **Taxable income: $2,695** | Federal tax (married, standard W-4): ~$220 | FICA: $206.17 | State tax (assume 4%): $107.80 | **Net pay: $2,161** (**69% take-home**).

**Employer payroll tax burden = 7.65% to 13%+ of gross wages** (varies by industry/state). **Breakdown of employer costs beyond gross salary**: **1.

FICA taxes (employer match)**: Employer pays **7.65% of gross wages** to match employee FICA: **(a) Social Security tax (employer)**: 6.2% on wages up to $176,100 in 2025. **Calculation**: Same as employee side (employer pays 6.2%, employee pays 6.2% = 12.4% total to IRS). **Example**: Employee earns $60,000 annual.

Employer Social Security tax = $60,000 × 6.2% = $3,720. **(b) Medicare tax (employer)**: 1.45% on all wages (no limit). **Example**: $60,000 × 1.45% = $870. **Total employer FICA**: $3,720 + $870 = $4,590 (7.65% of $60,000). **Key difference from employee**: Employer does NOT pay Additional Medicare Tax (0.9% on wages over $200k) - only employee pays that. **2.

Federal Unemployment Tax (FUTA)**: **6.0% on first $7,000 of wages per employee** (reduced to 0.6% with state credit). **How FUTA works**: (1) Gross FUTA rate: 6.0% on wage base of $7,000 = $420 max per employee. (2) **FUTA credit**: If employer pays state unemployment tax (SUTA) on time, gets 5.4% credit → Net FUTA = **0.6%**. (3) **Max FUTA per employee**: $7,000 × 0.6% = **$42 per year**. **When you pay more**: If you are in a **credit reduction state** (state has outstanding federal UI loan), the 5.4% credit is reduced.

Example: California, New York had credit reductions in 2023-2024 due to pandemic UI debt → Net FUTA up to 3.3% instead of 0.6%. **Example**: Employer with 10 employees (all earn $50,000+).

FUTA = 10 employees × $42 = $420 total annual. **3.

State Unemployment Tax (SUTA/SUI)**: **0.5% to 10%+ on state wage base** (varies dramatically by state and employer experience rating). **How SUTA works**: (1) **State wage base**: Range from $7,000 (AZ, CA) to $56,500 (WA) in 2025. (2) **Tax rate**: Based on **experience rating** (employer's history of unemployment claims).

New employers: Typically 2.5-3.5% (assigned new employer rate).

Established employers: 0.5-5% (good record) or 5-10%+ (high turnover, many claims). (3) **Calculation**: Employer wage base × SUTA rate. **Example 1 (California)**: Wage base: $7,000 | New employer rate: 3.4% | SUTA per employee: $7,000 × 3.4% = $238. **Example 2 (Washington)**: Wage base: $68,500 (2025) | Average rate: 1.5% | SUTA per employee: $68,500 × 1.5% = $1,027.50. **Example 3 (Texas)**: Wage base: $9,000 | New employer rate: 2.7% | SUTA per employee: $9,000 × 2.7% = $243. **High-cost states for SUTA**: Washington ($1,000+/employee), New Jersey, Massachusetts (high wage bases + rates). **Low-cost states**: Arizona, California, Florida, Tennessee (low $7,000-$10,000 wage bases). **4.

Workers' Compensation Insurance**: **0.5% to 15%+ of gross payroll** (varies by industry risk classification). **How workers comp premiums work**: (1) **Classification code**: NCCI assigns codes based on job duties (e.g., 8810 Clerical, 5645 Carpentry, 8742 Sales). (2) **Rate per $100 of payroll**: Set by state and insurer based on injury risk.

Low-risk (office): $0.20-$1.00 per $100 payroll (0.2-1%).

High-risk (construction, logging): $10-$50 per $100 payroll (10-50%). (3) **Calculation**: (Gross Payroll ÷ 100) × Rate. **Example 1 (low-risk office)**: $60,000 payroll | Rate: $0.50 per $100 | Premium: ($60,000 ÷ 100) × $0.50 = $300 (0.5% of payroll). **Example 2 (high-risk construction)**: $60,000 payroll | Rate: $15 per $100 | Premium: ($60,000 ÷ 100) × $15 = $9,000 (15% of payroll). **States with highest workers comp costs**: California, New York, Hawaii (strict regulations, high injury costs). **States with lowest costs**: Texas (optional coverage for private employers), Indiana, Arkansas. **5.

Employer-sponsored benefits (optional but common)**: **(a) Health insurance**: Employer typically pays 70-80% of premium.

Average cost: $7,000-$8,000/year per employee (single) or $20,000+/year (family) in 2025. **Example**: Family plan costs $22,000/year.

Employer pays 75% ($16,500), employee pays 25% ($5,500 via pre-tax payroll deduction). **(b) Retirement plan match**: 401(k) match typically 50% of first 6% contributed = **3% of salary cost**. **Example**: Employee earns $60,000, contributes 6% ($3,600).

Employer matches 50% of that = $1,800 (3% of $60,000). **(c) Paid time off (PTO)**: Average 15-20 days (3-4 weeks) = **6-8% of productive time** (employer pays for non-working days). **(d) Other benefits**: Life insurance ($20-$50/employee/year), disability insurance (1-3% of payroll), tuition reimbursement, commuter benefits. **Total employer cost example (California, office worker, with benefits)**: Employee gross salary: $60,000 | Employer FICA match (7.65%): $4,590 | FUTA (0.6%): $42 | SUTA (3.4% on $7,000): $238 | Workers comp (0.5%): $300 | Health insurance (employer share): $7,000 | 401(k) match (3%): $1,800 | **Total employer cost: $73,970** (**123% of base salary**). **Breakdown**: Base salary: $60,000 (100%) | Payroll taxes: $5,170 (8.6%) | Benefits: $8,800 (14.7%) | **True cost to hire: $73,970**. **Industry variations**: (1) **Low-cost industries** (tech, professional services): 115-125% of salary (low workers comp, moderate benefits). (2) **High-cost industries** (construction, manufacturing): 130-150%+ of salary (high workers comp, union benefits). (3) **Retail/hospitality**: 110-120% (part-time workers, fewer benefits). **Employer tax filing requirements**: (1) **Form 941** (Quarterly Federal Tax Return): Report wages, federal income tax withheld, FICA.

Due: April 30, July 31, October 31, January 31. (2) **Form 940** (Annual FUTA Return): Report unemployment taxes.

Due: January 31. (3) **State quarterly returns**: SUTA and income tax withholding (varies by state). (4) **Year-end**: W-2 forms to employees by January 31, W-3 to SSA. **Penalty for late payroll tax payment**: IRS penalties = 2% (1-5 days late), 5% (6-15 days), 10% (16+ days), 15% (10+ days after IRS notice). **Plus**: Daily interest (8% annual rate in 2025). **Trust Fund Recovery Penalty**: 100% of unpaid employee withholding (income tax + employee FICA share) can be assessed personally against business owners/officers. **Example**: Employer withholds $5,000 from employee paychecks but fails to remit to IRS → Owner personally liable for $5,000 + penalties.