Every freelance community keeps a list. It lives in group chats, private Slack channels, and quiet warnings passed between designers, developers, and agency owners. The names on it belong to clients who take the work, praise the work, and then sit on the invoice for sixty, ninety, sometimes a hundred and twenty days.
Maximiliaan van Kuyk thinks that list belongs in the open.
His company, IOU Marker, built in Miami and currently in beta, gives every client and every service provider a public Trust Score based on how they behave after a contract is signed. Pay on time and the score rises. Pay late and it slips. Ghost an invoice and it drops hard. The company is now opening a seed round on the bet that reputation, not another reminder email, is what finally gets people paid.
The scale of the problem is not in dispute. Remote’s 2025 Contractor Management Report found that 85 percent of freelancers have their invoices paid late at least some of the time. For just over 21 percent, late payment is the norm rather than the exception, arriving more than half the time or not at all. On the business side, the 2025 Intuit QuickBooks Small Business Late Payments Report found that 56 percent of American small businesses are owed money on unpaid invoices, an average of $17,500 each. Nearly half of them report invoices sitting past due by more than thirty days.
What the numbers hide is who absorbs the damage. Most clients never refuse to pay. They pay eventually, after the second reminder or the third, and the delay costs them nothing. The freelancer waiting on the money covers rent, payroll, and credit card interest in the meantime. One side treats the invoice as a line item. The other side treats it as groceries.
Van Kuyk, a serial entrepreneur, kept running into that imbalance in different industries. A PR agency owner spent six months chasing a final balance. A web developer billed a large client and had to keep nudging them about the open invoice. A small production company waited on a brand client who kept insisting the check was cut.
“You can be good at what you do and still lose money because someone else is bad at paying,” van Kuyk said. “That shouldn’t be how this works.”
His diagnosis is that the invoice is the wrong place to intervene. By the time a bill goes out, the leverage is gone. If nothing holds a client accountable for paying on time, the rational move is to protect their own cash flow at the expense of everyone downstream. So IOU Marker starts earlier, at the agreement itself.
The platform handles countersigning, either on a service agreement template it provides or on a contract the user uploads. AI reads the document, extracts the payment terms, and schedules the invoices. When the work ships, the invoice goes out automatically with a payment link attached. Follow-up messages, written with the context of the specific deal, go out before due dates pass. The chasing stops being the business owner’s evening chore and becomes the software’s job.
Then comes the score. IOU Marker’s Trust Score works the way ratings do on Airbnb, where hosts and guests review each other and a bad record follows you. The team noticed that payment disputes already spill into public view when they turn ugly, surfacing on X, LinkedIn, and private industry groups. The score gets ahead of that moment by making payment behavior visible before a deal is signed, not after it collapses.
The company is also meeting deals where they actually happen. Most informal agreements start in WhatsApp or Slack, so IOU Marker is building AI agents that operate inside both. A contract can be sent, signed, and invoiced without anyone leaving the thread. If a due date passes, an agent in the same chat handles the follow-up. Nobody has to draft another “just checking in” message and read it four times to make sure it sounds friendly but not desperate.
“Most freelancers or small business owners aren’t bad at their work,” van Kuyk said. “They’re bad at the part where they have to be a contract lawyer, accounts receivables, and an accountant all in the same afternoon. We’re trying to take those tasks back off their plate.”
The Trust Score is where the idea stops being a workflow tool and starts being a fight. Large companies have spent years building accounts payable departments around the comfort of paying on their own schedule. Extended terms are a working capital strategy, not an accident. A public record of payment behavior threatens that arrangement, and some clients will resist it hard. Whether they can afford to resist once enough freelancers check scores before signing is the question the company is raising money to answer.
For the people doing the waiting, the appeal is simple. Right now a client’s payment history exists only in the memory of whoever they hired last. When a relationship sours over money, it sours privately. The contractor moves on, the client moves on, and the next freelancer walks into the same trap with no warning. A score that travels changes that math. Good payers build a visible asset. Bad payers build a visible liability.
The timing works in the company’s favor. Independent workers now account for close to half of the global labor force, and most of the financial tools they rely on were designed for large companies. Early coverage has come from Refresh Miami, Impact Wealth, and GigWise as the product moves out of beta.
Van Kuyk describes the larger goal as a permanent record of professional behavior, the kind that already exists for borrowers and landlords but never for clients.
“Right now, the only person who knows you pay late is the person waiting on the money,” he said. “When we are at scale, that will not be the case. It will become much harder to run an operation that systematically pays late or stiffs people.”
The whisper network was never a solution. It was a symptom. IOU Marker is betting that once the whispers become a score, the checks start clearing on time.
