Is there a legal deadline for paying an invoice?

Not universally. The deadline depends on what you agreed to (contract or invoice terms). If you state Net 30 on the invoice, that's the legal deadline. If there's no stated term, the law might require 'reasonable time,' which varies by state and industry.

What happens if an invoice isn't paid by the due date?

You can pursue late payment remedies: send demand letters, charge late fees (if stated in your contract), pursue small claims court, or hire a collection agency. You may also be able to stop providing services until payment is made.

Do different states have different invoice payment laws?

Yes. Some states have 'prompt payment laws' that require payment within a certain timeframe (often 30 days for government contracts, 45-60 days for private contracts). Check your state and industry regulations.

How Many Days Do You Have to Pay an Invoice? Legal Answer

The legal deadline depends on what you agreed to beforehand. Without a written agreement, laws vary by state and industry. Understanding these rules protects you if a client doesn’t pay and helps you pursue remedies.

The Basic Legal Rule: What You Agreed To

Simple rule: a client must pay by the due date you specified. If you invoice with “Net 30,” the legal deadline is 30 days after the invoice date.

Without a specified term, the law requires payment within a “reasonable time.” That depends on:

Industry norms (retailers expect 5 days; contractors expect 30)
Service type (consulting allows longer than repairs)
Prior dealings with the client
Local laws and business customs

Most courts define “reasonable time” as 10 to 60 days, depending on context.

State-Specific Prompt Payment Laws

Many states have “prompt payment” laws with set timelines:

California: Most service contracts are due within 30 days unless you agree otherwise.

New York: Generally 30 days, unless the contract says differently.

Texas: No state-wide law for private contracts, but you can set your own terms.

Illinois: 30 days for construction and repair work.

Federal Contractors: Must pay subcontractors within 7 days of receiving payment from government.

Check your state’s laws. If you work with government, federal prompt payment laws usually apply and require payment within 30 days.

What “Net 30” Means Legally

Net 30 means 30 calendar days (not business days) from the invoice date. Invoice May 28, due date is June 27.

The client is legally obligated to pay by June 27. If they don’t, you can pursue remedies like small claims court or demand letters.

Some invoices specify “Net 30 business days” (excluding weekends and holidays). This extends the deadline to about 42 calendar days. Be specific to avoid confusion.

Legal contract signing lawyer — Clear invoice terms create legal obligations for timely payment

Late Payment Consequences

If unpaid by the due date, you have legal options:

Send a demand letter: A formal letter stating amount, invoice number, and due date, requesting payment within 10-15 days. This signals seriousness and often prompts immediate payment.

Charge late fees: If your contract states “1.5% interest per month overdue,” you can charge it. Track days late and add the fee.

Report to credit agencies: You can report the client to business credit agencies, damaging their credit. Rare but an option for very late payments.

Stop services: For ongoing work, pause until they catch up if they stop paying.

Small claims court: For invoices under your state’s limit (often $5,000-$25,000), file in small claims. Simple and no attorney needed.

Hire a collection agency: For larger invoices, hire a collection agency. They take a percentage of what they collect.

Sue in civil court: For large unpaid invoices, hire an attorney and sue for breach of contract.

Small Claims Court for Unpaid Invoices

Small claims court is accessible for most freelancers and small business owners. The process:

File a claim in your local court
Provide invoice and proof of work (emails, signed agreements)
Attend a hearing to present your case
Judge awards the amount owed if you win
Client pays or you pursue wage garnishment

Costs are low (usually $50-300 filing fee) and no attorney needed. Many freelancers successfully recover this way.

Protecting Yourself: Payment Terms in Contracts

The best protection is a written contract with payment terms before work starts. Include:

“Payment terms: Net 30 days from invoice date.” “Late payment will accrue interest at 1.5% per month.” “Work will not be delivered until payment is received.” (if applicable)

This creates a legal obligation and grounds for legal action if they don’t pay.

Invoices with unclear payment terms are harder to enforce legally. Always state the due date explicitly on your invoice and contract.

What Overdue Means

An invoice is overdue the day after the due date. Net 30 due June 27 means overdue on June 28.

After 30 days overdue, it’s significantly past due. After 60 days, severely past due. Most businesses write off anything past 90 days.

Track days overdue carefully. This number determines late fees and whether to pursue legal action.

Collecting Overdue Invoices

Steps to collect:

Day 5 overdue: Send a friendly reminder. “Hi, I haven’t received payment for invoice #2026-001, due on June 27. Could you check the status?”

Day 15 overdue: Send a formal email or letter. “As of [date], invoice #2026-001 for $2,500 remains unpaid. Please remit within 10 days or I will pursue legal remedies.”

Day 25 overdue: Send a demand letter via certified mail. This shows seriousness and creates a legal record.

Day 30+ overdue: Consider small claims court, collection agency, or cease services.

Document everything: emails, calls, letters. This helps in court.

Industry-Specific Laws

Construction: Most states have mechanics’ lien laws allowing contractors to place liens on property if unpaid. Timelines vary.

Government work: Federal Prompt Payment Act requires payment within 30 days for federal contracts.

Professional services: Most states allow interest on overdue invoices, but check yours.

Retail: Retail usually expects immediate payment, not Net 30.

Know your industry’s standards.

Negotiating Terms With Slow-Paying Clients

If clients pay late, adjust your terms:

Request upfront payment before work begins Reduce terms from Net 30 to Net 15 Add a late fee clause Require a deposit

These protect your cash flow and signal you’re serious about timely payment.

International Payment Terms

If you invoice internationally, laws vary by country. Clarify terms in writing and specify which country’s laws apply.

Many require payment within 45-60 days. Some require local currency, adding conversion risks. Work with a contract attorney if you invoice internationally.