Documents for new employees: I-9, W-4, and DE 4

You are about to hire your first helper, or your fifth, and you do not know what paperwork to ask for. Many contractors start with a handshake and fix the paperwork later. That is where the problems start.

This guide is for construction business owners who hire employees in California and the U.S. You will see the 7 most common groups of documents, with the deadlines you need to know, especially those for Form I-9.

This is an informational and educational guide, not legal advice. What your business needs may vary, so confirm the details with a labor attorney or the official agency.

In short

• The employee fills out section 1 of the I-9 no later than the first day of work. You complete section 2, generally, within 3 business days.
• The W-4 (federal) and the DE 4 (California) are used to calculate payroll tax withholding.
• In California, you must report each new employee to the EDD within 20 days of their first day of work.
• Keep every signed document in an organized file.

1. Form I-9: eligibility to work in the U.S.

The I-9 (Employment Eligibility Verification) is a federal USCIS requirement, the immigration agency. It confirms the employee's identity and permission to work. Every new employee must have one, regardless of origin.

The deadlines, according to USCIS, are these:

• Section 1 (completed by the employee): no later than the first day of work. They can do it earlier, but only after accepting the offer.
• Section 2 (you fill it out): generally within 3 business days after the first day of work. If the person will work fewer than 3 business days, it must be completed no later than the first day.

Example: your roofing helper starts on Monday. On Monday he fills out section 1. You review his original documents and complete section 2 no later than Thursday.

The employee chooses which documents to present from the official I-9 list. You cannot demand a specific document. A copy of the I-9 is kept for the period USCIS specifies; confirm the time frame on its site.

2. Forms W-4 and DE 4: tax withholding

The IRS Form W-4 (Employee's Withholding Certificate) tells your payroll how much federal tax to withhold from the paycheck. The employee fills it out with their tax filing status and, if they want, extra adjustments. Since 2020, the form no longer uses "exemptions" or "allowances."

In California, Form DE 4 is also used for state withholding. You can find it on the EDD forms page (Employment Development Department).

If the employee doesn't turn in a W-4, the IRS sets default withholding rules. Ask for it before the first payment.

3. Personal and contact information

You need the basics to pay and report correctly:

• Full legal name, address, phone, and email.
• Social Security number (SSN), needed for payroll and tax reports.
• Date of birth, to confirm the minimum legal age to work.
• Emergency contact, very useful on jobs where there is a risk of accidents.

Keep this information in a safe place with limited access.

4. Bank information for direct deposit

If you pay by direct deposit, you need the employee's routing and account number. In California, this normally requires the employee to authorize it in writing and voluntarily. If they don't want it, they are paid by check.

5. Offer letter, handbook, and agreements

• Offer letter: position, pay, start date, and basic terms. Employment is often "at-will," but this depends on the case.
• Employee handbook acknowledgment: a signature confirming the employee received the company policies (schedule, safety, equipment use).
• Confidentiality or other agreements: in California, some agreements, such as non-competes, have strict legal limits. Have an attorney review them.

Also, in California there are written notices you normally must give when you hire, such as the pay terms notice. Ask your lawyer or the DIR (Department of Industrial Relations) which ones apply to your case.

6. Benefits and deduction authorizations

If you offer health insurance, a retirement plan, or other benefits, keep the signed enrollment forms. Any paycheck deduction, such as an insurance premium, must have the employee's written authorization. Deductions have strict rules in California; confirm them before you apply them.

7. Background check (if you do one)

If you are going to run background checks, you need the candidate's signed authorization. The federal FCRA (Fair Credit Reporting Act) and California and local laws regulate how and when to do it. Talk to an attorney before you build your process.

New employee reporting in California

Besides the employee's paperwork, you must report each new employee to the state registry. The EDD states that the report (Form DE 34) is due within 20 days of the first day of work. It is easier to file online.

What to do now

• Create a file for each employee with the 7 groups of documents.
• Put the I-9 dates on your calendar: first day and 3 business days.
• Ask for the W-4 and DE 4 before the first payroll.
• Report the new employee to the EDD within 20 days.
• Keep the I-9 separate from the other documents in the file.

When to talk to a professional

Talk to an employment attorney if you have questions about immigration documents, agreements, or background checks. Talk to a tax preparer, CPA, or enrolled agent for withholding questions. For payroll, work with a specialized provider or partner.

If the worker could also be a subcontractor, first read 5 key points to determine whether someone is an employee.

How ODC helps you

At Oficina del Contratista, we keep your books up to date with bookkeeping for contractors, so every paycheck is recorded in order. For payroll, we connect you with independent partners on our payroll page. ODC does not give legal or tax advice.

References

1. USCIS: Completing Section 1 of Form I-9 — I-9 deadlines and rules
2. IRS: About Form W-4 — what the W-4 is and how federal withholding works
3. California EDD: Payroll tax forms and publications — state forms such as the DE 4
4. California EDD: New Employee Registry FAQ — reporting new employees within 20 days

This article is for information and education only. It is not legal, tax or bookkeeping advice. We are a bookkeeping service: for tax matters, consult a tax preparer, CPA or enrolled agent.