How to Keep One Slow-Paying Customer From Running the Whole Quarter

One customer can keep the crew busy and still put the quarter in a hole. The work looks fine. The invoice is out. The money does not come in on time. Payroll, materials, and the next job still have to be funded.

That is not a collections lecture. Year-end collections covers working the whole list of open invoices. This is a concentration problem. If too much of Q4 cash depends on one slow payer, that customer is running the quarter.

How to Tell If One Customer Owns Your Cash

Run the receivables aging report by customer, not just in total. Then look at three numbers for the largest name on it:

• Share of what is unpaid. Divide that customer's open balance by total open receivables. If one name is a large share, the quarter is exposed to that one payer's habits.
• How old it is. A big balance that pays on schedule is a large customer. A big balance that keeps sliding into the older aging columns is a slow one.
• What is still going in. Add the labor and materials already spent on that customer's current work that have not been billed yet. That money is out of the bank too.

Then ask one question: would the next 30 days get tight if that customer's check did not arrive? If yes, the issue is bigger than one late invoice.

There is no universal percentage that counts as too much. Pick a threshold that fits your payroll and reserve, and decide in advance what happens when a customer crosses it. Building a cash reserve covers sizing the buffer that has to cover that gap.

What Usually Happens Next

• You keep working because the relationship feels important
• New costs go out before old invoices come in
• Other customers get less follow-up because this one job is loud
• October and November feel tight even when the P&L still looks busy

What to Do Before That Customer Runs Q4

1. Separate the relationship from the cash

A good customer can still be a slow-paying customer. Treat the unpaid invoices as a cash item, not as a personal slight. A plain conversation about when the open balance will be paid is part of running the account, not a threat to it.

2. Stop adding new costs blindly

If older invoices are unpaid, think before putting more labor and materials on that same account. More work does not fix a collection problem. It makes the balance you are waiting on bigger, and you fund it in the meantime.

3. Keep the rest of the list moving

Do not let one loud account freeze everyone else. Current work still gets billed on time, and the smaller, cleaner invoices still get followed up. The step-by-step version of that review is in year-end collections.

4. Decide what new work you will take from them

If they want another job while prior invoices are sitting, the terms have to change before the work starts: a deposit, a shorter billing cycle, or a pause until the account is current. Put the change in writing with the new job, not after it is underway. That is not being difficult. That is keeping one customer from running the quarter. If a deposit is part of the new terms, handling customer deposits explains how to keep it from inflating profit.

How KDM Accounting Services Can Help

At KDM Accounting Services, we help Florida contractors see when one account is carrying too much of the cash. We can:

• Break open receivables out by customer and by age
• Show how much of Q4 cash depends on one name
• Flag unbilled work and new costs piling up on the same account
• Connect receivables to the next 90 days of cash

The goal is to see the exposure early, while you still have room to change terms or slow the spending.

Busy With One Customer Is Not the Same as Funded

Q4 is short. If one slow-paying customer is holding a large share of what you are owed, the rest of the quarter has to be managed around that fact. Bill the other work. Follow up on the open balance. Think before adding more cost to the same account.

If you want a clearer picture of which customers are holding Q4 cash, contact KDM Accounting Services. We'll help you break the receivables out before one account runs the quarter.

Related reading

• Year-End Collections: Getting Paid Before the Calendar Turns
• What Contractors Should Tighten Up Before October 1
• Building a Cash Reserve for a Contracting Business
• Cash Flow Forecasting Basics for Florida Contractors
• How Progress Billing Affects Cash Flow
• Bookkeeping services