The Net-30 Survival Guide for Subcontractors

A net-30 subcontractor who treats those 30 days as free credit to the general contractor is doing business on a tightrope with no net. The real cost of net-30 on a $25,000 electrical rough-in is $750 to $1,500 in hidden financing, lost opportunity, and stress. You survive it by planning for the gap before you pull the first foot of wire, not by hoping the check clears on day 31.

If you bill $600,000 a year on net-30 and your average payment actually lands at day 45, you are floating roughly $74,000 worth of labor and material all year long. That is your cash. You finance it every month, whether you want to or not. This guide is about taking control of that float: negotiating terms that shrink it, using lien rights as leverage, bridging gaps without 24% credit cards, and building a buffer so one slow-paying GC doesn't empty your tool account.

Key takeaways

• Treat net-30 as a line of credit you extend to the GC: know exactly what it costs you in dollars.
• Get a signed draw schedule that breaks the job into sub-$5,000 chunks you can invoice weekly.
• File a preliminary notice the day you sign the contract; it protects your right to lien and often puts you at the front of the pay line.
• Open a dedicated cash buffer account and move 5% of every check into it until you have a two-payroll cushion.
• When a GC hits day 35, send a formal notice of intent to lien. It costs nothing and gets results.

What does “Net 30” actually cost a subcontractor?

Net-30 means the GC owes full payment 30 days after they receive your invoice. On paper it is a one-month float. In the field it usually stretches past 45 or 60 days. That delay is not just an annoyance. It is a direct cost that comes out of your margin.

Start with the cash you front. On a $15,000 HVAC rough-in, you might spend $6,000 on equipment, $3,500 on labor, and $1,000 on small materials, permits, and fuel before you mail the first bill. That is $10,500 out of your pocket. If the check arrives on day 50, you have carried $10,500 for seven weeks. Even at an 8% small-business line of credit, the interest on that float is about $80. If you use a factoring company at 3% per 30 days, the cost jumps to $315. Put it on a credit card at 22% APR and you lose over $300 in a hurry, plus the card payment cycle.

The bigger hit is what you cannot do with the money. While $10,500 is tied up, you cannot buy material for the next job at a cash discount, take on a fast-paying T&M call, or cover payroll without pulling from reserves. That missed opportunity costs you more than the interest.

The table below shows how the true cost climbs when net-30 turns into net-45 or net-60. It assumes a $15,000 contract with $10,500 in up-front costs and an 8% cost of capital.

The numbers are not theory. Ask any electrical sub who did a 200-amp panel swap for $3,500, spent $1,200 on the panel and breakers the same day, paid a journeyman $500 for the install, and waited 62 days to get paid. That sub lost at least $18 to capital cost and forfeited the ability to buy wire at a 2% net-10 cash discount on the next job. The panel swap looked profitable on paper. The payment terms ate the extra margin.

How can I negotiate better subcontractor payment terms upfront?

Payment terms are a negotiation item, same as scope and price. The time to talk about money is before you swing a hammer. Most subcontractors skip it because they fear losing the job. The GC expects you to ask, and the ones worth working for will make reasonable concessions.

Start by asking for a detailed draw schedule. Instead of one final invoice after punch-out, break the job into milestones tied to physical progress. A four-month custom-home rough-in for an electrical sub might look like this:

• 10% at contract signing — mobilisation and to release initial material orders
• 25% after underground rough-in — slab conduit, grounding, and temporary power
• 25% after top-out rough-in — walls open, all boxes and home runs in, before insulation
• 25% after trim-out — devices, panel terminations, and fixtures in place
• 15% after final inspection and as-built drawings delivered

None of those chunks exceeds $7,500 on a $50,000 contract. Every two to three weeks a check should land. You are never floating more than two to three weeks of labor.

Ask for a material deposit on the front end. On a $40,000 design-build HVAC change-out, the equipment alone can run $18,000. A plumbing contractor doing a $30,000 rough-in for a restaurant will drop $9,000 on cast iron pipe and fittings before the first full day on site. A 50% material deposit, paid at contract signing, shifts that float onto the GC. Many GCs will agree if you show them the supplier invoice. Some will pay the supplier directly, which still keeps cash out of your hands but removes the financing burden.

Offer a 2% prompt-pay discount in exchange for 15-day terms. That means you discount the invoice 2% if the check arrives within 15 days instead of 30. Most contractors price 2% into the job from the start, so the discount does not cut into your margin; it simply rewards the GC for doing what you want. A $25,000 invoice becomes $24,500 if paid in two weeks. The GC gets a small win; you get cash in hand and cut your float cost by half.

Put these terms in the subcontract. A three-sentence clause beats a handshake every time:

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“Owner shall pay Subcontractor according to the Draw Schedule in Exhibit B. Payments not received within the specified time shall bear a service charge of 1.5% per month (18% APR). If any payment is fifteen days past due, Subcontractor may suspend work until payment is received.”

That language is common in standard AIA subcontracts. It gives you the right to stop work and charge interest without filing anything. Most slow-paying GCs fix the check as soon as you mention stopping a framing crew over a payment dispute.

What should I do during the job to get the final check fast?

Most final-payment delays are not about money. They are about paperwork. The GC’s accounts payable person needs lien waivers, certified payroll, as-built drawings, signed change orders, and a clean punch list. If one item is missing, the check sits in a drawer.

Treat close-out paperwork as part of your scope. On day one, ask the project manager what they need for the final pay application. It is usually a list of five or six documents. Build a manila folder for each job and drop copies in as you go.

Invoice as soon as the milestone is met, not at the end of the month. If you finish the underground rough-in on a Tuesday, send the invoice Tuesday night. The GC’s draw cycle might be monthly, but getting your number in the system early means it hits the next check run.

Use job photos to head off disputes. A “substantial completion” milestone can turn into a week of back-and-forth over a missing strap. Send four clear photos with the invoice: panel interior, exterior disconnect, stub-ups, and a wide shot of the area. The GC’s project manager can approve it from their phone. No visit, no argument.

For big jobs, get a weekly signed field ticket. It takes 90 seconds: date, hours worked, brief scope, signature from the GC’s super. If the GC ever questions progress, you have a stack of signed slips.

One HVAC sub I know changed his close-out process and cut his average days-to-pay from 55 to 38. His entire secret: he submits a one-page close-out checklist with every final invoice, showing that lien waivers, refrigerant logs, operation manuals, and startup reports are attached. The accounts payable clerk does not have to chase him. His check goes to the top of the pile.

How do I use lien rights without burning bridges?

Mechanics lien rights are the strongest payment tool you have. Using them does not mean you file a lawsuit. It means you follow a step-by-step process that signals, “I know the rules, and I will get paid on time.”

Start with a preliminary notice. In most states, this is a simple document you send to the property owner and the GC at the beginning of the work that preserves your right to file a lien later. A plumbing sub in California, for example, must serve a “20-day preliminary notice” within 20 days of first furnishing labor or materials. Even in states where it is not required, sending a pre-lien notice makes you visible to the owner and lender. That visibility alone often moves you to the front of the pay line when the draw comes.

When a payment is late, use a notice of intent to lien. This is a letter stating that you intend to file a mechanics lien if payment is not received by a specific date, typically 10 days out. It is not filed with the court. It goes to the GC, the owner, and sometimes the lender. The language is direct: “If the amount of $12,430 is not paid by March 20, we will file a mechanics lien against the property at 124 Oak Street.”

I have seen this work faster than any phone call. A concrete sub in Texas filed an intent to lien on a $14,000 residential basement. The homeowner had no idea the GC was behind on payments. The owner called the GC at 8 a.m. the next morning. The concrete sub had a wire transfer by noon. No lien was actually filed. The relationship survived because the sub gave a clear deadline and did not jump straight to a lawsuit.

The table below walks through a quiet escalation that protects cash without burning bridges.

The key is to file preliminary notices on every job automatically. When that becomes your standard practice, it is not a threat. It is company policy. GCs quickly learn that you are organized and will not be the sub they can pay last.

Bridging the cash gap: funding that won’t ruin your margins

Sometimes the float stretches and you need cash to cover payroll, buy material for the next job, or handle a slow season. The wrong move is pulling out a 22% credit card or raiding your personal savings. Those choices turn a payment delay into a long-term debt problem.

Here are the realistic options ranked from cheapest to most expensive, based on a $20,000 gap you need to bridge for 45 days.

Invoice factoring works for many subcontractors who have no reserves and time-sensitive payroll. A factor buys your unpaid invoice and gives you 85% of it now, then the remaining balance minus their fee after the GC pays. On a $25,000 invoice factored at 3% per 30 days over 60 days, the fee is $1,500. That is expensive, but less expensive than missing a payroll and losing two good workers to a competitor. The lesson: factor only the invoices you have to, while you build a cash reserve so you can stop factoring.

The best bridge is a business line of credit set up when you do not need it. Talk to your bank or a credit union that knows construction. Get a $30,000 line in place, draw on it only for true cash-flow gaps, and pay it down as soon as the check clears. The cost is a fraction of factoring and your credit stays clean.

How to build a cash buffer so Net-60 won’t break you

A cash buffer is not a luxury for slow years. It is the tool that lets you turn down bad work, switch GCs, and survive a winter slowdown. Without it, you are dependent on the next draw and the next GC’s mood.

Start with a separate business savings account. Do not try to keep the buffer in your operating account. The money will evaporate into fuel, parts, and lunch receipts. Open a free savings account at a different bank so it takes one extra step to transfer.

Move 5% of every customer payment into that account until you reach a target equal to two full payrolls plus one month of shop overhead. For a crew of five with a $15,000 weekly wage bill and $8,000 in fixed costs, the target is $38,000. That sounds big. It is built $400 at a time on a $8,000 check.

Some contractors build faster by selling unused tools and equipment, dumping the truck with the blown transmission, or taking a few high-margin T&M weekend jobs they pay to the buffer account directly. An electrical contractor in Ohio built a $25,000 buffer over two years simply by putting every lighting retrofit job payment straight into the buffer account until the target was hit.

Once the buffer is funded, you have breathing room. A GC whose net-30 stretches to net-60 becomes an annoyance, not a disaster. You can make payroll without panicking. You can buy material with a cash discount instead of a 30-day supplier account that costs 2% more. The buffer becomes a competitive advantage.

What to do the moment a GC pays late

Late payment is not your fault, but your response determines whether you get paid in three days or three months. Do not wait and hope. The day after a payment is due, move.

1. Check the contract — Confirm the payment date, required documentation, and any notice provisions. Make sure you did not miss a required lien waiver or W-9 that holds up the draw.

2. Send a short professional reminder — Email the project manager or accounts payable contact. Subject: “Invoice #1240 — Past Due $11,750.” Body: “This invoice is now past due per our subcontract. Please let me know what is needed to release payment. I have attached a copy and the signed field tickets.”

3. Make a call within three days — Skip the email back-and-forth. Call the GC’s super or PM. Ask specifically: “Is there a paperwork hold-up or a funding issue?” The answer tells you what to do next. Paperwork you can fix quickly. A funding issue means you escalate to the owner.

4. Send a notice of intent to lien at day 35 or 45 — Your state’s deadline for filing a lien runs from the last day of work, not from the invoice date. Do not lose your rights while waiting. The notice of intent often loosens payment within a week.

5. Stop work if your contract allows it — Most subcontracts let you suspend work for non-payment after written notice. A drywall crew that stops hanging board on a 6,000 sq ft house gets attention fast.

6. Know when to hire a construction attorney — If the GC is ghosting you, the amount is over $10,000, and you are approaching your state’s lien deadline, pay a lawyer for a demand letter and a lien filing. It costs $500–$1,500 and tells the owner and lender that this is serious.

Frequently asked questions

Can I charge interest on overdue invoices from a GC?

Yes, if the subcontract allows it. Add a clause that unpaid balances carry a service charge of 1.5% per month (18% APR) or the maximum allowed by state law. Collecting that interest requires consistent follow-up; many subs treat it as a negotiation lever rather than a revenue stream. The mere presence of the clause encourages on-time payment.

What is the difference between a preliminary notice and a mechanics lien?

A preliminary notice is a document you send at the start of work to preserve your right to file a mechanics lien later. It does not encumber the property. A mechanics lien is a legal claim filed with the county recorder after you are unpaid, giving you a security interest in the property. You generally cannot file a valid lien without having sent the notice first.

How long should I wait before filing a mechanics lien?

Do not wait until you are desperate. Most states give you a window of 60 to 120 days from your last day of work to file a lien. Start the pre-lien process at day 35 or 45, with a notice of intent, and be prepared to file the actual lien by day 60. Waiting until the deadline risks losing your right to a sub who filed three days earlier.

Can a GC blacklist me for filing a lien?

Some GCs will, but the ones who blacklist a sub for protecting his right to be paid are the ones who habitually pay late. Many organized GCs expect subs to send preliminary notices. Sending a notice of intent is softer than filing a lien and rarely damages a relationship if the communication stays professional and factual.

Should I stop work if the GC is 60 days past due?

If your subcontract allows suspension for non-payment and you have properly notified the GC in writing, stopping work is a powerful tool. It is not a bluff. Demobilize safely, secure your materials, and document everything. A two-day shutdown often resets the conversation. Come back only after you have a written payment commitment or a cashier’s check.

Is factoring right for a small subcontractor?

Factoring can work when you lack cash reserves and face payroll deadlines. You sell an invoice for immediate cash, typically 85% of its value, and the factor takes a fee. It is expensive (2–4% per 30 days) and should be a short-term bridge. Use it sparingly while you build an operating reserve so you can eventually stop factoring.

How do I tell a new GC I want payment terms faster than net-30?

Frame it around project efficiency. Say, “I price my work assuming 15-day terms after milestone completion. That lets me keep material costs tight and pass the savings to you. If net-30 is standard, I will need to add 2% to cover my float costs.” Most GCs will choose the lower price and agree to the faster terms once they understand the math.

Keep the money side simple so you can stay on the tools

Surviving net-30 terms is a skill, same as bending conduit or sweating pipe. It comes down to four habits: negotiate draws upfront, send preliminary notices like clockwork, keep a cash buffer you never touch, and treat late payments with a system instead of emotion. Every subcontractor who does these things stops worrying about payday and starts controlling their business.

The paperwork that supports those habits does not have to eat your evenings. This is where a tool like Krue makes sense for a contractor who would rather be on the jobsite than in a QuickBooks screen. Krue handles estimates, invoicing, payment reminders, and preliminary-notice tracking from your voice or a few taps. It keeps you organized on the money side so you can focus on the rough-in, the trim, and the next bid. See if it fits your truck at https://krue.app.