Surety has a ratio paradox. It is one of the best-performing lines in insurance and one of the most expensive to run. “When you look at the Surety industry, particularly within the contract bond space, the best news is that we have the lowest combined ratios,” says Vinod Kachroo, Head of Americas at Tinubu. “The challenging part is that we have high expense ratios.”
Surety contract bond work is still largely manual, and most of it falls to people whose time is worth more elsewhere. Underwriters spend their days chasing financial statements and WIP schedules, confirming documents belong to the right principal, and checking what else a contractor has in their portfolio. The judgment they were hired for comes last, after time (and thus money) has been spent elsewhere.
The expense ratio problem is really a workflow problem. Fix the hand-offs in the workflow and the number follows. That is where Tinubu has focused recent engineering efforts, starting inside the carrier. The company has three new AI-native capabilities built from the ground up for contract bonds, all shaped by customer feedback: an Underwriter Workbench, a rebuilt Rating Engine, and a modern UI.
"What Tinubu is doing is attacking that expense ratio by generating a much higher level of efficiency," Kachroo says. "We are doing it by leveraging completely modern technology, including agentic AI, to help drive automation and quick, effective decision-making."
In contract bonds, this efficiency will bring greater upside than anywhere else in Surety. The values are larger, the timelines run longer, and the risk has to be watched continuously over time, rather than assessed once. And because Tinubu runs systems on both sides of a bond, for carriers and the agencies, this is only the first piece of a workflow built to connect them.
From Chasing Data to Making Decisions
From first submission by a broker to a workable underwriting file, an underwriting decision takes at least two weeks of time. The Underwriter Workbench cuts those two weeks to about two hours. The saving comes from automating the acquisition, assembly, and organization of documents, so underwriters can spend their time on risk assessment.
“We are moving an underwriter from being a person who does the work of data collection to being a decision maker,” Kachroo says. “We are also making it easier for them to look at risk across a portfolio and over time, rather than just one bond at a time.”
That shift happens because the Workbench brings the full intake and analysis workflow into one place. The financial and WIP analysis is assembled before anyone opens the file, so the underwriter receives a package to assess rather than build, with exposure across the book visible alongside the single bond.
A 720-Degree View
“We are collecting what I call the 720-degree view of the data,” Kachroo says. “360 degrees of internal data and 360 degrees of external data. We combine them and create an analytical view for the underwriters.”
It starts at ingestion. AI classifies each document, confirms it belongs to the correct principal, and maps the fields into an underwriter-friendly format. Balance sheets, income statements, and the ratios underwriters use are calculated without anyone opening a spreadsheet. That picture includes margin fade, the slow erosion of a contractor’s gross profit across reporting periods.
WIP schedules and margin fade are contract bond problems specifically, and margin fade is among the strongest warning signs an underwriter has. Finding it has traditionally meant hand-building comparisons from archived folders. Now the Workbench surfaces it automatically.
Two more contract-specific gaps close the same way. Active project locations plot to a map, so a contractor overextending across regions, or a carrier’s exposure concentrating in one, is visible at a glance. And checking government sources for what other contracts a principal is carrying now runs automatically.
The file also stays current. Status Inquiries keeps WIP data flowing in on the carrier’s schedule, so what supported the decision does not go stale.
Embedded, Not Bolted On
“Everybody in the market is now claiming they are doing AI,” Kachroo says. “But many of them are doing what I call bolt-on AI, which is adding AI to what they do today. You can generate a little bit of efficiency that way. But what we are doing is embedding AI in what you do: AI, including agentic AI, is built into the technological foundation. That’s what helps us get to the next level.”
The distinction matters most in contract bonds, where submissions arrive as unstructured financials and WIP schedules that must be interpreted rather than looked up. Bolt-on AI will not handle that well, if at all. “We are helping our customers completely reimagine their processes and their business models,” Kachroo says, “not just make them better or more efficient.”
Combined Capabilities
“Underwriting is the heart of what we do,” says Kachroo. “Rating is the heartbeat. And user experience is how we do the dash to the finish line. All three work together. That is why we launched the three capabilities together: they go hand in hand and complete the full life cycle of bond management, rather than just an aspect of it.”
The rebuilt Rating Engine handles the moment an agent asks how a bond was priced. Most rating systems today, says Tinubu Senior Product Manager Destry Gustin, are “kind of a black box.” Now every component of a premium is a visible line item, calculated in real time. Overrides sit on top of the original calculation rather than replacing it, so removing one snaps the baseline back.
Overrides can be applied at tier level as a percentage, an absolute figure, or a total, with tier detail visible so commission and billing stay correct. For the underwriter, explaining a price becomes a glance rather than a manual reconstruction, and every judgment call carries its own record. The full breakdown flows downstream, so billing and accounting agree with the bond without manual reconciliation.
Kachroo calls this the layered pricing model, and it works because it is wired into the same workflow. A contract bond moves from intake to issuance in a single workspace, with a human in the loop on every decision and the handoffs and redundant data entry taken out.
The Highway Ahead
Everything above happens inside the carrier. Tinubu has also rethought what happens between carriers and the agencies that bring them business, where the same documents currently get re-keyed at every handoff. That cost hits hardest on contract bond submissions, since they're among the largest and most complex packages of all.
That's the problem the Digital Highway is built to solve. “Our digital highway integrates the agency workflow and the agency processes with the carrier processes to create an end-to-end, streamlined workflow, and ensures that carriers and brokers automatically have the same information,” says Kachroo. “There should be no need for emails or phone calls, and agents should be able to do their business on an iPad as they are sitting in front of a principal and be able to write a bond end to end.”
For carriers, the payoff is what arrives on the other end. A direct connection between the agency system and the carrier system means bond data will move from submission to issuance without being re-typed at any point, so the transcription errors that come from manual re-entry won't happen in the first place. Rate changes will flow to agents automatically too, which means fewer bonds written against stale numbers and less rework for underwriters to catch downstream.
This works because Tinubu builds for both sides. The same company behind the Underwriter Workbench, Rating Engine, and UI also runs the agency and broker system on the other end of the connection. The reconciliation work that would normally land on someone at the carrier or the agency instead gets handled by the systems themselves.
Full, automated integration is where this is heading, and contract bonds are where it starts.
The Underwriter Workbench, rebuilt Rating Engine, and new UI are live now with our first carrier partner. The Digital Highway is what will connect that work to agencies.
Surety’s combined ratios are already the best in insurance. Its expense ratios no longer have to be the worst.
