Payroll Processing
Purpose
Every employee and contractor must be paid correctly and on time, with all tax withholdings, benefits deductions, and compliance filings handled accurately. This skill calculates gross-to-net pay, applies federal/state/local tax tables, handles benefits deductions, and prepares the payroll register for review. Without it, payroll errors lead to compliance penalties, employee dissatisfaction, and cash flow surprises.
When to Use
- "Run payroll for this period"
- "Review payroll before processing"
- "Calculate net pay for these employees"
- "Process contractor payments"
- "File payroll taxes"
- "Update benefit deductions"
Inputs Required
- Employee roster — name, salary/hourly rate, pay frequency, tax withholding elections (W-4), benefit elections, state of employment.
- Pay period data — hours worked (hourly), PTO taken, commissions/bonuses earned, expense reimbursements.
- Prior payroll register — last period's numbers for sanity check.
- Tax rate tables — federal, state, local for each employee location.
- Benefits elections — health, dental, vision, 401(k) deferrals, HSA/FSA.
Quick Reference
| Calculation |
Formula / Rule |
Why It Matters |
| Gross Pay (Salaried) |
Annual salary / Pay periods per year |
Base for all deductions |
| Gross Pay (Hourly) |
Hours worked × Rate (OT at 1.5× over 40 hrs) |
Accurate for variable-hour employees |
| Federal Income Tax Withholding |
IRS Pub 15-T tables based on W-4 and taxable wages |
Largest single withholding; errors trigger penalties |
| FICA (Social Security + Medicare) |
SS: 6.2% up to wage base / MC: 1.45% (0.9% additional over $200k) |
Mandatory employer + employee portions |
| Benefits Deductions |
Pre-tax: 401(k), medical, HSA / Post-tax: Roth 401(k), life insurance |
Correct treatment prevents tax filing errors |
| Net Pay |
Gross − Taxes − Deductions + Reimbursements |
What employees actually receive |
| Total Employer Cost |
Gross pay × 1.25–1.4× (incl. employer taxes, benefits, workers comp) |
True cost of headcount for planning |
Procedure
1. Gross Pay Calculation
- Salaried: annual salary / pay periods. Prorate for mid-period hires/terminations.
- Hourly: hours worked × rate. Overtime at 1.5× for > 40 hours.
- Commissions: apply the commission plan. Validate against deals closed.
- Bonuses: apply the bonus formula. Confirm eligibility and approval.
- Contractors: flat amount per invoice, NO tax withholding.
2. Tax Withholding
- Federal income tax: IRS Pub 15-T tables based on W-4 elections, pay frequency, taxable income.
- Social Security: 6.2% up to the annual wage base.
- Medicare: 1.45% + 0.9% additional above $200k.
- State income tax: per-state tables.
- Local taxes: where applicable (NYC, SF, etc.).
3. Benefits Deductions
- Pre-tax: 401(k), medical/dental/vision premiums, HSA, FSA, commuter.
- Post-tax: life insurance, disability, Roth 401(k).
- Employer contributions listed separately.
4. Net Pay = Gross − Taxes − Deductions + Reimbursements
5. Payroll Register Review
Generate a payroll register:
| Employee |
Gross |
Federal WH |
FICA |
State WH |
Benefits (Pre) |
Benefits (Post) |
Net Pay |
Employer Taxes & Benefits |
| ... |
... |
... |
... |
... |
... |
... |
... |
... |
- Flag any net-pay anomalies: change > 20% from prior period, zero net pay (garnishment/error), negative net pay.
- Verify total employer-side taxes and benefits: FICA match (~7.65%), FUTA, SUTA, 401(k) match, health insurance contribution.
6. Payment & Filing
- Present the payroll register for human approval.
- After approval, prepare the journal entry: debit salaries/benefits/taxes expense, credit cash/bank, credit tax liabilities.
- Filing calendar hand-off to
tax-compliance-management for: 941 (quarterly), 940 (annual), state quarterly filings, W-2/W-3 (annual), 1099-NEC (annual).
Output Format
Payroll Summary:
- Total gross payroll
- Total net pay to employees
- Total employer taxes
- Period-over-period change (headcount and dollars)
- Runway impact
Done Criteria
The skill is complete when:
- Gross pay is calculated correctly for all employees and contractors (salaried, hourly, commission, bonus)
- Tax withholdings are applied using current federal, state, and local tables
- Benefits deductions (pre-tax and post-tax) are applied correctly
- Net pay is calculated and anomalies are flagged
- Employer-side taxes and benefits costs are calculated and documented
- The payroll register is presented for human approval (not auto-disbursed)
- Journal entry is prepared for hand-off to
ledger-management
Pitfalls
- Misclassifying employees as contractors (1099 vs W-2): If they work full-time, on your schedule, with your equipment → they're likely an employee. Misclassification carries heavy penalties
- Using outdated tax tables: Tax withholding tables change annually. Always use the current year's IRS Pub 15-T and current state tables
- Forgetting multi-state withholding: Withholding by state based on physical work location, not company HQ. Remote employees trigger nexus in their state
- Ignoring bonus supplemental rate: Federal supplemental rate is flat 22% for bonuses under $1M. Using regular withholding tables over-withholds
- Skipping period-over-period comparison: Not comparing the register to the prior period. A sudden 20% swing in net pay for an employee is usually an error worth catching before disbursement
- Auto-disbursing without human approval: Processing payroll directly to the bank without a review step. Payroll errors are expensive and embarrassing — always present for review first
Verification
Is each employee's gross pay calculated correctly based on their pay type (salaried, hourly, commission)? Are tax rates verified against current tables for each employee's work location? Are pre-tax and post-tax deductions applied to the correct income basis? Is the payroll register compared to the prior period for anomaly detection? Is the register presented for human approval before any disbursement?
Example
Example 1: Standard Payroll Run
User: "Run payroll for the bi-weekly period ending April 18 — we have 12 employees and 3 contractors"
→ You load the employee roster, pull W-4 elections and state info, collect timesheets for hourly employees and commission data for sales, calculate gross pay ($124,500 total), apply federal/state tax withholding ($31,200), apply benefits deductions ($8,900 pre-tax, $2,100 post-tax), compute net pay ($82,300), calculate employer-side taxes and benefits ($18,675), flag one employee with a 35% net pay increase (bonus included — confirmed), and present the full payroll register for human approval with a total cash outflow of $100,975 (net pay + employer taxes).
Example 2: Contractor Payment Run
User: "Process May contractor payments — 5 contractors totaling $28,000"
→ You verify each contractor's invoice against their agreement, confirm no tax withholding applies (all 1099-NEC eligible), run a quick worker classification check (all are genuinely independent — separate schedule, own tools, multiple clients), present the payment summary for approval, and note the 1099-NEC tracking requirement for year-end filing.
1---2name: payroll-processing3description: Run payroll end-to-end — gross-to-net calculations, tax withholding, benefits deductions, contractor payments, and compliance filings.4license: MIT5---6
7# Payroll Processing
8
9## Purpose
10
11Every employee and contractor must be paid correctly and on time, with all tax withholdings, benefits deductions, and compliance filings handled accurately. This skill calculates gross-to-net pay, applies federal/state/local tax tables, handles benefits deductions, and prepares the payroll register for review. Without it, payroll errors lead to compliance penalties, employee dissatisfaction, and cash flow surprises.
12
13## When to Use
14
15- "Run payroll for this period"
16- "Review payroll before processing"
17- "Calculate net pay for these employees"
18- "Process contractor payments"
19- "File payroll taxes"
20- "Update benefit deductions"
21
22## Inputs Required
23
241. **Employee roster** — name, salary/hourly rate, pay frequency, tax withholding elections (W-4), benefit elections, state of employment.
252. **Pay period data** — hours worked (hourly), PTO taken, commissions/bonuses earned, expense reimbursements.
263. **Prior payroll register** — last period's numbers for sanity check.
274. **Tax rate tables** — federal, state, local for each employee location.
285. **Benefits elections** — health, dental, vision, 401(k) deferrals, HSA/FSA.
29
30## Quick Reference
31
32| Calculation | Formula / Rule | Why It Matters |
33|------------|---------------|---------------|
34| Gross Pay (Salaried) | Annual salary / Pay periods per year | Base for all deductions |
35| Gross Pay (Hourly) | Hours worked × Rate (OT at 1.5× over 40 hrs) | Accurate for variable-hour employees |
36| Federal Income Tax Withholding | IRS Pub 15-T tables based on W-4 and taxable wages | Largest single withholding; errors trigger penalties |
37| FICA (Social Security + Medicare) | SS: 6.2% up to wage base / MC: 1.45% (0.9% additional over $200k) | Mandatory employer + employee portions |
38| Benefits Deductions | Pre-tax: 401(k), medical, HSA / Post-tax: Roth 401(k), life insurance | Correct treatment prevents tax filing errors |
39| Net Pay | Gross − Taxes − Deductions + Reimbursements | What employees actually receive |
40| Total Employer Cost | Gross pay × 1.25–1.4× (incl. employer taxes, benefits, workers comp) | True cost of headcount for planning |
41
42## Procedure
43
44### 1. Gross Pay Calculation
45
46- **Salaried**: annual salary / pay periods. Prorate for mid-period hires/terminations.
47- **Hourly**: hours worked × rate. Overtime at 1.5× for > 40 hours.
48- **Commissions**: apply the commission plan. Validate against deals closed.
49- **Bonuses**: apply the bonus formula. Confirm eligibility and approval.
50- **Contractors**: flat amount per invoice, NO tax withholding.
51
52### 2. Tax Withholding
53
54- **Federal income tax**: IRS Pub 15-T tables based on W-4 elections, pay frequency, taxable income.
55- **Social Security**: 6.2% up to the annual wage base.
56- **Medicare**: 1.45% + 0.9% additional above $200k.
57- **State income tax**: per-state tables.
58- **Local taxes**: where applicable (NYC, SF, etc.).
59
60### 3. Benefits Deductions
61
62- Pre-tax: 401(k), medical/dental/vision premiums, HSA, FSA, commuter.
63- Post-tax: life insurance, disability, Roth 401(k).
64- Employer contributions listed separately.
65
66### 4. Net Pay = Gross − Taxes − Deductions + Reimbursements
67
68### 5. Payroll Register Review
69
70Generate a payroll register:
71
72| Employee | Gross | Federal WH | FICA | State WH | Benefits (Pre) | Benefits (Post) | Net Pay | Employer Taxes & Benefits |
73|---|---|---|---|---|---|---|---|---|
74| ... | ... | ... | ... | ... | ... | ... | ... | ... |
75
76- Flag any net-pay anomalies: change > 20% from prior period, zero net pay (garnishment/error), negative net pay.
77- Verify total employer-side taxes and benefits: FICA match (~7.65%), FUTA, SUTA, 401(k) match, health insurance contribution.
78
79### 6. Payment & Filing
80
81- Present the payroll register for **human approval**.
82- After approval, prepare the journal entry: debit salaries/benefits/taxes expense, credit cash/bank, credit tax liabilities.
83- **Filing calendar** hand-off to `tax-compliance-management` for: 941 (quarterly), 940 (annual), state quarterly filings, W-2/W-3 (annual), 1099-NEC (annual).
84
85## Output Format
86
87**Payroll Summary:**
88- Total gross payroll
89- Total net pay to employees
90- Total employer taxes
91- Period-over-period change (headcount and dollars)
92- Runway impact
93
94## Done Criteria
95
96The skill is complete when:
971. Gross pay is calculated correctly for all employees and contractors (salaried, hourly, commission, bonus)
982. Tax withholdings are applied using current federal, state, and local tables
993. Benefits deductions (pre-tax and post-tax) are applied correctly
1004. Net pay is calculated and anomalies are flagged
1015. Employer-side taxes and benefits costs are calculated and documented
1026. The payroll register is presented for human approval (not auto-disbursed)
1037. Journal entry is prepared for hand-off to `ledger-management`
104
105## Pitfalls
106
107- **Misclassifying employees as contractors (1099 vs W-2)**: If they work full-time, on your schedule, with your equipment → they're likely an employee. Misclassification carries heavy penalties
108- **Using outdated tax tables**: Tax withholding tables change annually. Always use the current year's IRS Pub 15-T and current state tables
109- **Forgetting multi-state withholding**: Withholding by state based on physical work location, not company HQ. Remote employees trigger nexus in their state
110- **Ignoring bonus supplemental rate**: Federal supplemental rate is flat 22% for bonuses under $1M. Using regular withholding tables over-withholds
111- **Skipping period-over-period comparison**: Not comparing the register to the prior period. A sudden 20% swing in net pay for an employee is usually an error worth catching before disbursement
112- **Auto-disbursing without human approval**: Processing payroll directly to the bank without a review step. Payroll errors are expensive and embarrassing — always present for review first
113
114## Verification
115
116Is each employee's gross pay calculated correctly based on their pay type (salaried, hourly, commission)? Are tax rates verified against current tables for each employee's work location? Are pre-tax and post-tax deductions applied to the correct income basis? Is the payroll register compared to the prior period for anomaly detection? Is the register presented for human approval before any disbursement?
117
118## Example
119
120**Example 1: Standard Payroll Run**
121> User: "Run payroll for the bi-weekly period ending April 18 — we have 12 employees and 3 contractors"
122
123→ You load the employee roster, pull W-4 elections and state info, collect timesheets for hourly employees and commission data for sales, calculate gross pay ($124,500 total), apply federal/state tax withholding ($31,200), apply benefits deductions ($8,900 pre-tax, $2,100 post-tax), compute net pay ($82,300), calculate employer-side taxes and benefits ($18,675), flag one employee with a 35% net pay increase (bonus included — confirmed), and present the full payroll register for human approval with a total cash outflow of $100,975 (net pay + employer taxes).
124
125**Example 2: Contractor Payment Run**
126> User: "Process May contractor payments — 5 contractors totaling $28,000"
127
128→ You verify each contractor's invoice against their agreement, confirm no tax withholding applies (all 1099-NEC eligible), run a quick worker classification check (all are genuinely independent — separate schedule, own tools, multiple clients), present the payment summary for approval, and note the 1099-NEC tracking requirement for year-end filing.