Start with the employment model
Before choosing forms, identify the legal employer, taxpayer, immigration petitioner, agency, payroll provider and host site. The word “contractor” in a commercial conversation does not settle employee status. A UK coordinator’s duties differ from those of a US employer.
Federal employer and payroll setup
The responsible employer needs the applicable identification, tax accounts, deposit arrangements and reporting process. Separate onboarding documents, tax returns, payments and year-end reporting. Employers using an ordinary payroll processor generally retain tax responsibility; other third-party arrangements have different rules.
Official sources
State, local and worksite requirements
Use the state directory to find the relevant agencies, then check the worksite and employee-residence facts. Research unemployment, withholding, new-hire reporting, wage rules, workers’ compensation, local taxes and any applicable staffing/PEO or trade requirements. Public or federally assisted construction can introduce prevailing-wage and certified-payroll requirements.
Official sources
Insurance, safety and project controls
Confirm insurance for the actual employer, state, trade and construction exposure. Agree the staffing agency and host’s respective training, site-safety, incident and injury-reporting duties. Contracts do not erase responsibilities imposed by law. Keep eligibility, insurance, funding and site checks separate from marketing promises.
Official sources
Cross-border tax and money flows
Residence, visa status, treaties, social-security arrangements, travel reimbursements and benefits require fact-specific review. Map who pays wages and taxes and who holds funds. A future AmChex should obtain advice before handling client payroll money; an example website does not establish authority to do so.
Official sources
Federal forms & processes
This catalogue explains common roles. It does not determine which forms an individual project requires. Check current instructions, electronic-filing rules and deposit deadlines.
| Form / process | Purpose | Who acts |
|---|---|---|
| SS-4 / EIN application | Employer identification | Responsible employer or authorised applicant |
| I-9 | Employment eligibility verification; generally retained by the employer | Employee and employer |
| W-4 | Federal withholding instructions; supplied to the employer | Employee |
| 941 | Federal employment-tax return, generally quarterly; deposits are separate | Employer or authorised filer |
| 940 | Federal unemployment-tax return where applicable | Employer or authorised filer |
| W-2 / W-3 | Employee wage statements and transmission to SSA where applicable | Employer or authorised filer |
| 8655 / 2678 / 8973 | Different third-party arrangements; not interchangeable or universally required | Employer and relevant authorised provider |
W-9 and 1099 reporting may arise in a correctly established independent-contractor arrangement; they are not substitutes for employee onboarding or proof of work authorisation.
Explore the detailed US guides
Follow the federal checklist, then map the responsibilities around a proposed assignment.
The federal employer baseline
Start with the real employing relationship, work authorization and federal payroll duties, then add state, local and construction requirements.
Who does what in a US assignment
A practical research brief for a recruitment agency, actual employer, payroll partner and project host, using an illustrative AmChex coordination model.