The short answer
A client that makes up a large share of your revenue and pays late is your biggest credit risk, and usually the one you are least willing to confront. The way through is to replace the worry with a number and a limit, then raise it as a process change rather than a complaint. In order:
Work out your total exposure: overdue invoices, invoices not yet due, and work done but not yet invoiced.
Decide the most you are prepared to be owed at any one time, before you speak to anyone.
Find out whether the client has a cash problem, a process problem or a dispute.
Raise it with 2 people: the person who owns the relationship, and the person who controls payment.
Agree a plan in writing: dates for the overdue balance, and terms that keep new work from adding to it.
Keep working only while the balance stays under your limit.
The goal is to keep the account and cap how much it can cost you.
Why this is harder than any other late invoice
With a small client, a late invoice is an admin task. With a client worth 30% of your revenue, every follow-up feels like a risk to the business, so it gets softened, postponed or skipped. Meanwhile the work continues, the next invoice goes out, and the balance grows.
The pattern tends to follow the same shape. The client asks for patience once, with a good reason. Next time the delay is longer. Partial payments arrive, which feels like progress and keeps the conversation polite, while the oldest invoice stays unpaid. A 2023 r/Entrepreneur discussion about a consulting client 4 months behind includes owners describing exactly that slide, from one month pending to several.
Step 1: Work out your real exposure
The overdue invoices are only part of what is at risk. Add everything the client owes or will owe for work already done:
What the client owes | Example |
|---|---|
Overdue invoices | $30,000 |
Invoices sent but not yet due | $15,000 |
Work done this month, not yet invoiced | $7,500 |
Total exposure | $52,500 |
Then put it next to something you know. If your monthly payroll is $28,000, this client is holding almost 2 months of it. That comparison is what the conversation is really about, and it is far easier to act on than a general sense that things are slipping.
Step 2: Set a limit before you talk to them
Decide the most this client can owe you at any one time. A practical starting point is one month of their billing, or the largest amount you could lose without missing payroll, whichever is lower. Then decide what happens when the balance reaches it: the next phase waits for payment, or new work is invoiced in advance.
Set the limit once, while you are calm, and let it make the decision later. A limit decided in the middle of a difficult call tends to come out higher.
Step 3: Find out why they are late
The fix depends on the cause, and the signals are usually visible once you look for them.
A process problem
Invoices are approved but paid on the client’s own schedule, or stuck waiting for a purchase order or an approver. The client is solvent and the money is parked. The 7 reasons invoices stall and what to do when finance is handling it cover this case.
A cash problem
Payments arrive in odd, partial amounts rather than whole invoices. Promises come with a reason instead of a date. Your contact mentions cutbacks elsewhere. This is the case where a limit matters most, because the balance you are carrying may not come back in full if the client’s position gets worse. In a 2025 r/smallbusiness thread about a wholesale customer worth around 30% of revenue and paying in partial amounts, several commenters read the partial payments as a sign of financial strain.
A dispute
The client has an objection to the work that has not been said out loud. It shows up as vague dissatisfaction, requests for extra revisions before paying, or a new contact questioning the scope. Follow the dispute process for this one, because more payment follow-ups will not resolve it.
Step 4: Talk to the 2 people who matter
Your day-to-day contact owns the relationship. Someone in finance or accounts payable controls when you are paid. With a large client they are rarely the same person, and raising it only with your contact puts the pressure on someone who may not be able to fix it.
Frame it as capacity and process: explain what you can carry and ask for a plan. Send it to your contact, and ask to be introduced to whoever handles supplier payments:
Subject: Keeping [project] on schedule
Hi [Name],
We’re currently at [amount] across [number] invoices, the oldest dated [date]. At that level we can’t keep carrying the work forward without a plan to bring the balance down.
Could we agree a date for the overdue invoices, and set up the next ones so they reach your payment run on time? If it would help, I’m happy to spread the older balance over your next [number] payment runs.
Could you also introduce me to the person who handles supplier payments, so I can check we have everything they need?
Thanks,
[Name]
Send it from your billing address so the payment side of the conversation stays out of the project thread. If you would rather not be the person sending it at all, separating the relationship from the payment thread is the whole reason Collected42 exists.
Step 5: Agree a plan in writing
The plan needs to cover the old balance and stop new work adding to it. The options, roughly from least to most change for the client:
Invoice before their payment run. For a process problem, this alone may fix it.
A payment plan for the overdue balance, with a date and an amount for each instalment.
New work paid in advance or on delivery until the account is current, alongside the payment plan for the old balance.
A retainer or deposit for ongoing work, invoiced before the month starts. The deposit guide covers how to present it.
Shorter terms for future invoices, set out in the next contract or statement of work.
Confirm whatever you agree in a short email with the dates in it. The cost worth naming: each option asks a client with more negotiating power than you to change something. Some will push back. Know which options you would accept before the call, and which one is your minimum.
A late fee is a weak tool here. A large client’s accounts payable team pays approved amounts, and a fee added afterwards needs its own approval. Whether late fees work covers why.
When to stop work
If the balance reaches your limit and there is no plan, pausing work is the step that protects you. Check what your contract allows first, and give written notice with a date. With a clause that allows it, you are applying terms the client signed. Without one, the conversation is harder, and it is worth taking advice.
The cost worth naming: pausing work for your biggest client may end the relationship. That is why the limit matters. Losing a client that owes you $15,000 is a setback you can plan around. Losing one that owes you $52,500 takes almost 2 months of payroll with it.
Make one client matter less
Track what share of revenue each client represents, and treat any client whose loss would stop you making payroll as a credit decision as well as a sales one. The more other work you have, the easier it is to hold a limit calmly, and the less every follow-up to one client feels like a risk.
FAQ
What do I do if my biggest client keeps paying late?
Work out your total exposure, set the most you are willing to be owed, and find out whether the cause is a process problem, a cash problem or a dispute. Then raise it with both your contact and whoever controls payment, and agree a written plan for the old balance and for new work.
Should I stop work for a client who owes me money?
Pause work when the balance reaches a limit you set in advance and no plan is agreed. Check your contract first and give written notice with a date. Stopping without a clause that allows it is harder to justify, so take advice in that case.
How much should one client be allowed to owe me?
There is no single right figure. A practical starting point is the lower of one month of that client’s billing and the largest amount you could lose without missing payroll. Decide it before the client is late, not during the conversation.
How do I ask an important client to pay without losing them?
Present it as capacity and process: state the balance, ask for a date and a plan, and offer to spread the older amount if that helps. Involve the person who controls payment, not only your day-to-day contact, and keep the money conversation separate from the project thread.
Should I offer my biggest client a payment plan?
Often yes, for the overdue balance, as long as new work does not add to it. Put each instalment date and amount in writing, and pair the plan with new work paid in advance or on delivery until the account is current.
Not legal or tax advice. Payment law and enforceable interest rates vary by state and country — have your contract terms and any notice to pause work reviewed by your own lawyer before use.