Contractor Cash Flow Management: Why Busy Doesn't Mean Paid

Most contractors who go out of business weren't unprofitable. They had full schedules, decent margins, and jobs lined up for weeks. What killed them was cash flow — the gap between when they paid for materials and labor and when clients actually sent the check. Understanding that gap, and building a system to manage it, is the difference between a business that survives and one that doesn't.

Why Cash Flow Kills Profitable Contractors

Profit is what your books say at the end of the year. Cash flow is whether you can make payroll on Friday. You can be profitable on paper and still bounce a check — because profit counts invoices you've sent, not money you've received.

The typical contractor cash flow problem looks like this: you start a $15,000 job, buy $6,000 in materials on your card, pay your helper $1,200 for the week, and finish the job on Friday. The client says they'll pay "next week." Next week becomes two weeks. Meanwhile your card payment is due, your insurance auto-drafts, and you've already committed to another job that needs materials Monday morning.

That's not a profit problem. That's a timing problem. And it's fixable.

The Deposit Rule: Never Float the Materials Yourself

The single highest-leverage change most contractors can make is requiring a deposit before work starts. The standard range is 30–50% of the total job cost, collected before you order a single item.

For a $10,000 job with $4,000 in materials: a 40% deposit ($4,000) covers your materials before you spend a dollar of your own money. You're no longer funding the client's project — they are.

Some contractors resist this because they're afraid clients will say no. In practice, any client who refuses to pay a standard deposit is a client who will be slow to pay the final invoice too. The deposit filters out the problem clients before they become your problem.

Structure it in three parts for larger jobs:

• 30–40% upfront — covers materials, mobilization
• 30–40% at midpoint — keeps you liquid through the job
• 20–30% on completion — minimizes your exposure at the end

Invoice the Day the Job Is Done

Every day between job completion and invoice sent is money sitting in your client's account instead of yours. Most contractors wait until the end of the week, or until they "get around to it." On a net-30 invoice, that delay turns into net-37 or net-45 by the time the client pays.

The rule is simple: invoice the same day the job is complete. If you finished at 4 PM, send the invoice by 6 PM. The faster the invoice hits, the faster the clock starts, and the faster you get paid.

Use invoice software with automated payment reminders — most are $15–30/month and save that in chasing alone. Set reminders at 7 days, 14 days, and 21 days past due. The reminder does the awkward follow-up for you.

What to Track Every Week (The 3-Number System)

You don't need a finance degree to manage cash flow. You need three numbers, checked every Monday morning:

1. Cash on hand — what's in your business account right now
2. Receivables due in the next 14 days — invoices sent, not yet paid
3. Payables due in the next 14 days — what you owe: materials, subs, insurance, card payments

If cash + receivables > payables, you're fine for the next two weeks. If not, you know early enough to do something about it — collect faster, delay a non-critical purchase, or line up a credit facility before it's an emergency.

Most cash crises aren't sudden. They're visible 2–3 weeks out if you're looking. Most contractors aren't looking until it's Friday and payroll is short.

The Slow-Pay Client Problem

Some clients are structurally slow payers — property managers, insurance companies, general contractors with their own cash flow problems. If you work with any of these regularly, you need to price that in.

A net-60 payment on a $10,000 job means you're financing $10,000 for 60 days at whatever your cost of capital is. If that's a credit card at 22% APR, you're paying ~$367 to wait. Either charge more for those clients, require larger deposits, or factor that cost into your overhead rate.

The other tool is a late payment clause in your contract — typically 1.5% per month on overdue balances. Most clients won't trigger it, but it gives you a legal basis to collect it when they do, and it changes behavior: clients who know there's a penalty tend to pay on time.

Build a Cash Reserve Before You Need It

The target is 2–3 months of operating expenses in a separate business savings account that you don't touch for anything else. At $15,000/month in overhead, that's $30,000–$45,000 set aside.

That number feels large when you're starting. Build toward it: every month, take 10% of gross revenue and move it to that account before you spend anything else. At $20,000/month revenue, that's $2,000/month — the reserve builds in 15–20 months without feeling the pain all at once.

With a reserve, a slow-pay client or a gap between jobs is an inconvenience. Without it, the same situation is a crisis.

The 5 Moves to Improve Cash Flow This Month

1. Add a deposit requirement to your next 3 quotes. Start at 33%. See what happens — almost nothing, in most cases.
2. Invoice the day each job closes, not at the end of the week.
3. Add net-30 payment terms to every invoice if you haven't already. "Due upon receipt" leaves timing ambiguous.
4. Set up one automated payment reminder at 7 days past due. Takes 10 minutes, runs forever.
5. Check your 3 numbers every Monday. Cash on hand, receivables due, payables due. Build the habit before you need it to save you.