Every mid-market general contractor eventually faces the same fork in the road. A large subcontractor fails mid-project, and the question becomes who absorbs the cost of finishing the work. Two instruments answer that question differently: the traditional performance and payment bond, and Subcontractor Default Insurance, or SDI, the category Zurich pioneered in the 1990s under the SubGuard name. In 2026, with material prices still climbing and surety underwriters tightening their standards, choosing between them is a strategic decision that deserves more than a reflexive answer.
How SDI Actually Works
A surety bond is a three-party arrangement. The surety prequalifies your subcontractor, stands behind its performance, and investigates before paying a claim. SDI collapses that structure into a two-party first-party insurance policy between you and your carrier. You enroll subcontractors into the program, you underwrite them, and when one defaults you declare it and manage the completion yourself, drawing on the policy to fund the loss. The control is real, and so is the ownership of the risk that comes with it.
The Deductible, Co-Pay, and Aggregate
This is where the two instruments diverge most sharply. A bond carries no deductible; the surety pays from the first dollar up to the penal sum. SDI is built the opposite way. Per-loss deductibles typically run from $350,000 to $2 million, layered above that with a co-pay band of roughly $1 to $5 million on which you retain about 20 percent. Carriers will write per-loss limits up to $50 million and aggregate limits up to $150 million, but your own annual exposure is capped by an aggregate retention set at three to five times the deductible. The risk-transfer premium is modest, near $3.50 per $1,000 of enrolled value, against bond premiums that range from roughly 0.5 to 1.5 percent of contract value. The headline number illuminates only part of the picture; your retained layer is where the real economics live.
Prequalification Becomes Your Discipline
With a bond, a third party vets your subcontractor. With SDI, that fiduciary responsibility moves onto your desk. You surface the warning signs — high credit-line borrowing, negative cash flow, thin backlog, delayed payments to workers or suppliers — and you own the consequence if you miss one. This is why carriers generally reserve SDI for contractors with more than $75 million in annual subcontracted volume and the internal underwriting depth to support it. The program rewards discipline and punishes its absence.
When SDI Leads, and When It Doesn't
SDI tends to win when you enroll a broad book of work, run mature prequalification, and want direct control over how a default gets resolved rather than waiting through a surety's investigation period. Its coverage can reach completion costs, defective-work correction, and indirect losses, with a tail running up to ten years past substantial completion. Bonds lead in other situations: on public work where payment-bond protection for lower-tier suppliers is required by statute, on single large subcontracts where you want first-dollar coverage without a retained layer, and for contractors whose volume or balance sheet cannot absorb an aggregate retention. Marsh notes that seven carriers now underwrite SDI, so terms are more negotiable than in the single-provider era, yet the instrument still fits a specific profile.
Balance Sheet and the High-Cost Environment
SDI losses land on your income statement and your cash position before recovery. In a market where the Surety and Fidelity Association estimates a default costs 1.5 to 3 times the subcontract value, a single failure inside your retention can consume real runway. That risk is not abstract right now. IMA's Q1 2026 data shows construction input prices up 2.8 percent year over year, copper wire and cable up 22.3 percent, and 70 percent of contractors reporting tariff impact while only 40 percent have raised their bids. Thin subcontractor margins are precisely what turns a schedule slip into an insolvency. Meanwhile surety demand remains robust — the SBA guaranteed a record $10.6 billion in FY25, up 15 percent — even as underwriters grow more selective about credit and fraud.
None of this points to one universal answer, which is exactly why we treat it as a design problem rather than a product sale. Our four-step process moves from Strategic Discovery, where we map your subcontractor concentration and balance-sheet tolerance, through Risk Assessment and Solution Design, and into Ongoing Optimization as your backlog and the cost environment shift. The goal is a structure that fits your business this year, not a template borrowed from a contractor twice your size.
Used well, either instrument is a torch that illuminates hidden default risk before it reaches your bottom line. The intentional contractor chooses based on volume, control, and the strength of its own prequalification — not on the first number quoted.
— Ryan Mefford, President & Risk Advisor
Sources
- NASBP — Subcontractor Default Insurance: Use, Costs, Practices
- Stoel Rives — Surety Bonds vs. Subcontractor Default Insurance
- Marsh — The Rise of Subcontractor Defaults
- IMA Financial Group — Construction Markets In Focus, Q1 2026
- OneGroup — The Evolving Landscape of Surety Bonding in 2025
- U.S. SBA — Record Surety Bond Guarantees in FY25
- SFAA — Research & Statistics
- AXA XL — Subcontractor Default Insurance