Both answer the same question — what happens to me if a subcontractor fails halfway through the job — and they answer it in structurally opposite ways.
A subcontractor bond is a three-party guarantee. The sub buys it, a surety underwrites the sub, and the surety guarantees that sub's performance to you. Subcontractor default insurance (SDI) is a two-party insurance policy. You buy it, it covers your cost to complete when an enrolled sub defaults, and you carry a deductible and a co-participation share — and you take on the job of prequalifying every sub yourself.
| Subcontractor bond | SDI | |
|---|---|---|
| Instrument | Surety guarantee, three parties | Insurance policy, two parties |
| Who buys it | The subcontractor | The general contractor |
| Who is underwritten | The subcontractor, by the surety | The GC's prequalification program, by the carrier — then each sub, by the GC |
| Where the cost sits | Embedded in the sub's bid price | Direct premium on the GC's P&L, rated on enrolled subcontract values |
| GC's retained loss | None — no deductible | Deductible plus co-participation above it, inside a per-loss limit and program aggregate |
| Who controls the default | The surety investigates and elects its remedy | The GC steps in immediately and completes, then claims |
| Lower-tier subs & suppliers | Payment bond gives them direct rights | No rights whatsoever — they are not insureds |
| Satisfies public-work statutes | Yes, that is what the statutes contemplate | No |
The bond buys you an independent opinion and a deep pocket. Before the surety issues, someone outside your organization has read that sub's financial statements, work-in-progress schedule, bank line, and character references — the same review described in surety prequalification vs insurance underwriting. A sub who cannot get bonded has just told you something you would have paid dearly to learn later. And when a default happens, you have no first-dollar exposure. For the mechanics of the three bond types, see payment vs performance vs bid bonds and what a performance bond costs.
SDI buys you speed and control. When an enrolled sub walks off, you do not send a notice and wait for a surety's investigation before mobilizing a replacement. You mobilize immediately, keep the schedule, and settle up with your own carrier afterward. On a schedule-driven project with liquidated damages running, that difference is the entire argument for SDI.
Bond cost is real, but it arrives inside the sub's number, so most contractors never see it as a line item. SDI premium is invoiced to you. That visibility makes SDI look expensive in a way bonding does not, which is a presentation artifact rather than an economic one. The honest comparison is total cost of risk: SDI premium, plus the deductible and co-participation you realistically expect to absorb across a program period, plus the salary cost of running prequalification — against the aggregate bond cost buried in your bid pricing.
A bond has no deductible. SDI has a meaningful one, and above it a co-participation percentage so you and the carrier share the excess. That structure is deliberate: the carrier is insuring a portfolio it does not underwrite sub-by-sub, so it keeps you financially invested in your own prequalification discipline. It also means SDI is not a first-dollar product. Small, routine subcontractor problems stay yours.
Under a bond, the surety elects the remedy. It may finance the defaulting sub, tender a completing contractor, or pay. That process protects the surety's money and it takes time. Under SDI, you are in charge from the first hour — but you are also spending your own money first and arguing about its reasonableness later, which is why the notice provisions and the definition of default in the policy deserve reading before, not during.
This is the part contractors underestimate. An SDI carrier is not underwriting your subs — it is underwriting your ability to underwrite your subs. You will be expected to maintain a written prequalification program, apply it consistently, document it, and keep it current, and the carrier will audit against it. If your process is a phone call and a gut feel, SDI is not a cost decision, it is an infrastructure project.
The deeper point holds even on private work. A subcontractor payment bond gives lower-tier subs and material suppliers a direct claim against a surety. SDI gives them nothing — they are not insureds and have no rights under your policy. Replace bonds with SDI on a project and you have not removed lower-tier payment risk; you have moved it onto yourself, and unpaid lower tiers will come at your lien rights and your own prime bond instead. Bonding requirements are governed by statute and contract and vary by state and project type — confirm the specific requirement with counsel before structuring around it.
| SDI tends to fit | Bonding tends to fit |
|---|---|
| Large, steady annual subcontracted volume | Lumpy or seasonal volume |
| An existing, staffed prequalification function | A lean back office |
| Repeat subcontractor base you know well | New trades, new geographies, unfamiliar subs |
| Schedule-critical work where speed of replacement is everything | Public work, or owners who require sub bonds by contract |
| Balance sheet that can absorb a deductible without flinching | Contractors who need zero retained loss |
| Many small trades, aggregate attrition risk | Concentrated, single-source, long-lead scopes |
A written bonding threshold policy: subcontracts above a stated dollar figure get bonded, everything below is enrolled in SDI. Then trade-based carve-outs layered on top, requiring a bond regardless of dollar size when:
Whichever structure you pick, it only functions if the paperwork is enforced — which is a certificate and compliance tracking problem as much as an insurance one, and it sits alongside the indemnity and risk-transfer language and the additional insured requirements in your subcontract. Note also that neither SDI nor a bond touches insured perils — a sub's defective work claim still runs through the general liability tower, and physical damage to the work in progress runs through builders risk. On wrapped projects the analysis shifts again — see wrap-ups vs practice policies.
Being enrolled in a GC's SDI program is not a free pass. You are still being underwritten — expect a prequalification packet asking for financials, a WIP schedule, references, bank and supplier contacts, safety data, and your labor classification practices. Some GCs charge an enrollment fee or an SDI participation deduction against subcontract value, so read the insurance and enrollment articles and price them into the bid rather than meeting them at the first pay application. And enrollment in someone else's program builds none of your bonding capacity, so if public or bonded private work is anywhere in your plan, keep your own surety relationship and reviewed statements moving in parallel.
Most contractors get this decision framed by whoever sells one of the two products. We work both sides: Bettr Coverage handles the insurance program, and BettrBonds handles contract surety across the Southeast — so the recommendation isn't determined by which product we happen to carry. For most contractors under a certain subcontracted volume, a disciplined bonding threshold with real prequalification behind it beats an SDI program they cannot staff. For the ones large enough for SDI to make sense, the useful work is modeling the retained loss honestly and reading the manuscript form before signing it. One agency, one relationship, every line reviewed together.
Send us your subcontract insurance exhibit, your current bonding threshold if you have one, and a rough breakdown of annual subcontracted volume by trade. We'll model retained loss under both structures and tell you plainly which one your business is actually built for. No charge, no pressure to move.
Get a free coverage reviewA first-party insurance policy the general contractor buys to cover its own cost to complete when an enrolled subcontractor defaults. Two parties only — carrier and GC. It carries a deductible and a co-participation share above it, sits inside a per-loss limit and a program aggregate, and obligates the GC to run a written prequalification program the carrier approves and audits.
It is a guarantee, not insurance, and it has three parties: the sub as principal, you as obligee, the surety as guarantor. The sub buys it and the surety underwrites the sub independently before issuing. You carry no deductible — but you also do not control the timing once the surety begins its investigation and elects a remedy.
No. Miller Act and state Little Miller Act statutes require bonds on the prime contract and SDI is not a permitted substitute. Even privately, a payment bond gives lower-tier subs and suppliers direct rights against a surety; SDI gives them nothing, because they are not insureds under your policy. Confirm the specific statutory requirement with counsel.
Wrong frame — the costs sit in different places. Bond cost is embedded in the sub's bid; SDI premium is invoiced to you. Compare total cost of risk: SDI premium plus expected deductible and co-participation plus the cost of staffing prequalification, against the aggregate bond cost buried in your bid pricing.
Generally the excess cost to complete the defaulted scope over the unpaid subcontract balance, usually plus correction of the defaulted sub's defective work, and often acceleration and extended overhead at a sublimit. Forms are manuscripted, not standardized — liquidated damages, consequential damages, and design exposure are common restriction points. Read the default definition and the notice requirements before you declare anyone in default.
Yes, and most contractors do. A written bonding threshold by dollar value, plus trade carve-outs requiring a bond regardless of size for single-source or long-lead scopes, critical-path trades, and any sub working well above its historical project size.
You'll still be underwritten, just by the GC: financials, WIP, references, bank and supplier contacts, safety and insurance data. Check the subcontract for an enrollment fee or SDI participation deduction and price it in. And it builds none of your own bonding capacity, so keep your surety relationship active if bonded work is in your future.
For general information only. Not legal advice and not a quote or contract of insurance. SDI policy forms are manuscripted and vary substantially between carriers — the definition of default, notice requirements, covered cost categories, deductible and co-participation structures, sublimits, and program aggregates differ by program; read the form actually issued to you. Surety bond forms, obligee rights, and default remedies likewise vary by bond form and by surety. Statutory bonding requirements on public work, lien and payment bond claim rights, notice deadlines, and contractor licensing rules differ across Georgia, Florida, South Carolina, North Carolina, Tennessee, and Alabama and between federal, state, and local projects — consult your construction attorney before structuring or replacing a bonding requirement. Coverage subject to policy terms, limits, exclusions, and carrier and surety appetite.