Staffing agencies operate as the employer of record for temporary workers. This means the agency handles all payroll obligations including wages, tax withholding, unemployment insurance, and workers’ compensation. The client company gets the worker’s labor without the employment relationship or administrative burden.

For payroll, the process starts with timesheets. Workers submit hours worked at each client site, often through digital systems or paper timesheets approved by on-site supervisors. The agency then processes payroll based on those approved hours. This includes calculating gross pay, withholding federal and state taxes, deducting any benefits, and issuing payment. Most staffing agencies pay workers weekly since temporary workers expect quick payment.

The billing side mirrors payroll but with a markup. If a worker earns $18 per hour, the agency might bill the client $27 per hour. That $9 spread covers employer payroll taxes, workers’ comp premiums, overhead, and profit margin. Agencies invoice clients based on the same timesheets used for payroll, usually on a weekly or biweekly cycle.

The challenge is timing. Agencies pay workers every week but clients typically pay invoices in 30 to 60 days. This gap creates significant cash flow pressure, especially for growing agencies placing more workers. Many staffing agencies use lines of credit or invoice factoring to bridge this gap. Without proper cash management, an agency can be profitable on paper but run out of cash to make payroll.

Tracking matters at every level. The agency needs to know profitability per worker, per client, and per job type. If one client negotiated lower rates or a particular role has higher workers’ comp costs, margins shrink. Without detailed tracking, agencies often discover too late that certain placements lose money. Working with a Detroit payroll service familiar with staffing operations helps ensure nothing slips through the cracks.

Proper payroll processing for staffing agencies requires matching every hour worked to both a worker payment and a client invoice. When hours get approved differently on each side or timesheets get lost, the agency either underbills clients or overpays workers. Both hurt the bottom line.

Staffing agencies also deal with multiple tax jurisdictions. Workers might live in one county, work in another, and the agency itself might be based somewhere else entirely. Each location can have different withholding requirements. Getting this wrong leads to compliance issues and penalties that eat into already thin margins.