Labor Burden: What It Is and How Fab Shops Should Track It

Labor burden is the total cost of employing a worker beyond their base wage — including payroll taxes, insurance, benefits, and other employer-paid costs. For a fabrication shop, labor burden typically runs 25–40% on top of an employee's hourly rate, meaning a $25/hr welder actually costs $31–$35/hr when burden is included. Accurate job costing depends on using the burdened rate, not the base wage, when calculating labor cost per job.

What Counts as Labor Burden

Labor burden includes every employer-paid cost tied to a worker:

Mandatory costs (federal and state law):
- FICA (Social Security and Medicare) — 7.65% of wages, per IRS Publication 15
- Federal Unemployment Tax (FUTA) — 6% on first $7,000 of wages
- State Unemployment Insurance (SUTA) — rate varies by state and employer experience rating
- Workers' Compensation insurance — rate varies by job classification and state

Voluntary or plan-driven costs:
- Employer health insurance contributions
- Retirement plan contributions (401k match, SIMPLE IRA)
- Paid time off (vacation, sick time, holidays) — these hours are paid but produce no billable output
- Tools, PPE, and uniforms when employer-supplied

The Bureau of Labor Statistics Employment Cost Index tracks civilian compensation benchmarks, which shops can use to sanity-check their burden estimates against industry norms.

How to Calculate Labor Burden Rate

The burden rate is expressed as a percentage added to the base wage:

Burden Rate = (Total Annual Burden Costs) ÷ (Total Annual Base Wages) × 100

Worked example for a four-person welding crew:

A $25/hr base wage becomes $33.50/hr fully burdened.

Why Burden Rate Matters for Job Costing

Using unburdened wages for job cost estimates understates true labor cost by 25–40%. This produces quotes that look profitable on paper but lose money in production — one of the most common causes of margin erosion in job shops.

FabWise captures time per worker, per job, per task. When you export those hours to your payroll provider or job costing spreadsheet, you apply the burdened rate — not the base wage — to get accurate job cost. FabWise tracks who worked on what and for how long. Your payroll provider (ADP, Gusto, QuickBooks Payroll) handles the actual pay calculation and tax compliance; FabWise feeds them accurate time data.

Burden Rate vs. Overhead Rate

These are related but different:

• Labor burden rate covers employer costs directly tied to the worker (taxes, insurance, benefits).
• Overhead rate covers shop-wide costs not tied to a specific worker — rent, equipment depreciation, utilities, supervision time.

Some shops combine them into a single loaded labor rate for quoting simplicity. Others keep them separate for more granular job cost analysis. Either approach works; the key is consistency across estimates, actuals, and reporting.

Tracking Burden in Practice

The most reliable approach:

1. Calculate your burden rate annually when you have final payroll tax rates and benefits cost data.
2. Apply it consistently across all job cost estimates for the year.
3. Capture actual hours per job so you can compare estimated vs. actual labor cost. This is where the accuracy of time data matters — a worker charging hours to the wrong job corrupts the comparison.
4. Reconcile quarterly as workers' comp rates, benefit costs, or headcount changes.

FabWise gives you step 3 — accurate time records per job, with the audit trail to catch miscoded hours before they distort your job cost reports.

Frequently Asked Questions

What is a typical labor burden rate for a fabrication shop?

Most fabrication shops carry a labor burden of 25–40% above base wages. The range depends on your state (payroll tax rates vary), your benefits package, and your workers' compensation classification. A shop in a high-risk classification with a comprehensive benefits package will be at the high end; a shop with minimal benefits in a lower-risk state may be at the low end.

Should I use the same burden rate for all workers?

You can use a blended rate (one rate for all direct labor) or role-specific rates (separate rates for welders, machinists, fitters, etc.). Role-specific rates are more accurate but require more administrative work. Most shops with fewer than 50 workers use a blended rate for simplicity.

Is labor burden the same as overhead?

No. Labor burden is the employer-side cost associated with a specific worker's wages — payroll taxes, benefits, workers' comp. Overhead is the cost of running the shop that isn't directly attributable to a specific worker or job: rent, utilities, equipment depreciation, indirect labor. Both need to be allocated to jobs for accurate job costing, but they're distinct categories.