A contract that says "payment due upon completion" with no other structure gives you exactly one tool: asking nicely.
Contractors with solid payment terms clauses have three things going for them that the vague-contract crew doesn't:
- A leverage point before the job starts. A signed deposit = client's money already committed. They can't walk away without losing it.
- A paper trail that justifies collection action. Invoices with a clear, pre-agreed payment schedule are far more defensible in a dispute or mechanic's lien filing.
- A legal mechanism when the final payment stalls. States give contractors lien rights — but those rights are only as strong as the documentation that preceded the work.
The Deposit Structure: 25/50/25 vs. 33/33/34
The most common deposit structure in contractor agreements:
25/50/25
| Milestone | Amount | What it covers |
|---|---|---|
| Deposit (at contract signing) | 25% of total | Materials, mobilization, shop time |
| Midpoint payment | 50% of total | Labor as work progresses |
| Final payment | 25% of total | Completion, punch list, sign-off |
This works for most residential and light commercial jobs under $30K. It front-loads enough commitment from the client to cover your costs if they bail mid-job, while keeping the final payment substantial enough that they're motivated to close you out.
33/33/34
| Milestone | Amount | What it covers |
|---|---|---|
| Deposit (at contract signing) | 33% of total | Full materials order |
| Second payment (at rough-in/start) | 33% of total | Labor through midpoint |
| Final payment | 34% of total | Completion |
Use this for larger jobs ($30K–$100K+) where materials are a significant portion of the job cost and your supplier requires payment before delivery.
What about "50% upfront"?
Some contractors ask for half up front for every job regardless of size. It's not wrong, but for small jobs under $2,000 it's often unnecessary and can create friction. Keep deposit amount proportional to job size and your actual risk:
- Under $5K: 25–33% deposit is normal
- $5K–$25K: 30–50% deposit is justified
- Over $25K: Progress billing (see below) is usually better than a single large deposit
Net-15 vs. Net-30 vs. Net-45: What's Standard, What's Aggressive
"Net-30" is the default in most construction contracts. But "Net-30 from what date?" is the question that matters — and it's where most contractors leave money on the table.
Standard language:
Payment due within 30 days of invoice date.
Better language:
Payment due within 30 days of invoice date. Invoice deemed received on date of delivery confirmation (email or in-person).
"Date of invoice" is ambiguous — did you email it? Drop it in their mailbox? Hand it to someone at the front desk? Spell it out. Some contractors go further:
For contracts over $10,000: Net-15 from invoice date. For contracts under $10,000: Net-30 from invoice date.
This is reasonable. Larger jobs create bigger cash flow pressure on your end — it's fair to ask for faster turnaround on bigger invoices.
Avoid:
- "Due upon receipt" — means nothing legally without a defined receipt date
- "Payment due on completion" without specifying the completion trigger — clients will argue about what "complete" means
- No late fee language — some contractors are afraid to include it; don't be
Late Fees: What's Legal and How to Word It
Late fees are enforceable in most states — but only if they're written correctly. A late fee clause must:
- Be stated as a fixed amount or percentage (not "reasonable late fees")
- Not be punitive enough to be considered unconscionable by a court (generally stay under 1.5% per month / 18% annual)
- Apply from a clearly defined date (not "after a reasonable period")
Standard enforceable late fee language:
Payment not received within 30 days of invoice date is subject to a late fee of 1.5% per month (18% annual APR) on the unpaid balance. Client is responsible for all collection costs including reasonable attorney fees.
That last clause is critical — it means if you end up in collections or small claims, the client covers your legal costs if you win. It changes the calculus for clients thinking about stiffing you; now they're not just risking the invoice amount, they're risking their own legal exposure.
What most contractors get wrong: They write "1% per month" but don't specify that it compounds monthly or that it applies from the invoice date vs. the due date. Be specific.
What some states restrict: Some states cap late fees or require them to be reasonable relative to actual damages. Alaska, California, Florida, and Massachusetts have specific consumer protection statutes that affect late fee terms. For those states, keep the late fee at or below 1.5% monthly and consult the specific statute if you're doing significant commercial work.
Progress Billing: The Clause That Protects You on Long Jobs
For any job that spans more than 4–6 weeks, a progress billing clause prevents the scenario where you've got $20K of labor in a wall and the client decides they want to "discuss the final invoice."
What a progress billing clause needs:
- Trigger events — what milestones generate a payment request. Example: "25% payment due upon mobilization and material delivery. 50% due upon rough-in completion. Final 25% due upon substantial completion and sign-off."
- Time limits on disputes — clients should have X days to dispute a progress invoice before it's deemed accepted. Example: "Client has 5 business days to notify contractor in writing of any dispute regarding a progress invoice. Failure to dispute within 5 days constitutes acceptance."
- Work stoppage rights — if a progress payment is more than X days late, contractor may stop work without breaching the contract. Example: "If payment is not received within 10 days of the due date, contractor may suspend work until payment is received. Project timeline shall be extended by the duration of any such suspension."
How to Write the Payment Terms Clause So You Can Enforce It
Here's the actual language to put in your contract:
Payment Schedule. Contractor shall submit invoices at the milestones identified in Exhibit A. Client shall remit payment within 30 days of invoice date. Late payments are subject to a monthly charge of 1.5% on the unpaid balance (18% APR). In the event of collection action, client shall pay all reasonable attorney fees and costs.
Work Suspension. If any invoice is more than 10 days overdue, contractor may suspend work immediately without liability. Client remains responsible for all work performed through the date of suspension. Contractor shall provide written notice of suspension; work resumes upon receipt of full payment.
Dispute Resolution. Client has 5 business days from receipt of any invoice to notify contractor in writing of a dispute. Failure to notify within that period constitutes acceptance of the invoice in full.
This is 9 sentences. Not complicated. But it's the difference between a contract you can enforce and a suggestions document.
Written contracts with enforceable payment terms, deposit structures, late fee language, and work suspension clauses — built for your trade, ready to use.
Start free — get the Change Order Form → Get the Contractor Pack →Where Your State's Lien Laws Give You Additional Leverage
Payment terms clauses are civil obligations — if a client breaches them, you sue. But mechanic's lien laws are a separate enforcement tool, and they're sharper. Understanding when you have lien rights and how to preserve them matters more than most contractors realize.
The general rule (varies by state): In most states, if you give written notice to the property owner before starting work, and you have a written contract documenting the scope and payment terms, you have the foundation for a mechanic's lien if the client doesn't pay. The lien attaches to the property, not just the contract.
Key deadlines by state:
- California: Preliminary notice required within 20 days of starting work. Lien rights lost if notice not filed.
- Texas: Notice required within 3 months of first providing materials or labor. Must file lien affidavit within 4th month after last labor performed.
- Florida: Owner must receive a notice of intent to lien before filing. 30-day notice required before recording lien.
- New York: Notice of mechanic's lien must be filed within 8 months of last work. If you're a sub, different rules apply — notice to owner required before filing.
These are generalizations. Every state has specific deadlines and notice requirements that vary by your role (prime contractor vs. subcontractor) and the project type. Check your state before assuming you have lien rights — in many states, missing the preliminary notice deadline loses them entirely.
Quick Reference: Payment Terms Checklist
Before you sign a contract (or before you send one to a client), confirm:
- Deposit percentage matches job size and your material exposure
- Payment milestones are defined and specific (not just "due on completion")
- Late fee language is written: 1.5%/month, applies from invoice date, covers attorney fees
- "Invoice deemed received" is defined (email delivery = date sent)
- Dispute window is specified (5 business days is standard)
- Work suspension rights are written in (10 days overdue = you can stop)
- Preliminary notice deadline checked for your state before starting work
Related Resources
- How to Write a Change Order — scope changes are the #1 source of payment disputes; document them properly
- HVAC Contractor Templates — payment terms, contracts, and change orders for HVAC pros
- Roofing Contractor Templates — lien leverage, payment schedules, and roofing-specific contracts
- Plumbing Contractor Templates — progress billing and payment terms for plumbing contractors
- Electrical Contractor Templates — payment terms and invoice templates for electricians