How surety underwriting sets bonding capacity: the three Cs, CPA statements, WIP schedules, bank lines, indemnity, and single and aggregate limits.
Education only / verify at source / not legal or accounting advice. This guide explains how contract surety underwriting generally works in the United States and Canada, using federal regulations, Small Business Administration (SBA) rules and public education from surety industry associations. Global Guarantors publishes industry education. We aren't a surety, broker, insurer, accounting firm or law firm. Every surety sets its own underwriting standards, and we don't publish premiums, rates or capacity quotes.
Start here: Surety vs insurance and the indemnity agreement · Hiring a bonded contractor
A contractor that wants to bid bonded work soon asks: how much bonding can it get? The answer is its bonding capacity, a surety's judgment about how large a single job, and how much total work, it is prepared to back. Capacity is not a published tariff. It comes out of underwriting, a review of the contractor's people, track record, finances and backlog that looks more like a bank credit decision than an insurance quote.
This guide walks through that review, how single-job and aggregate limits work, how capacity grows, the SBA's Surety Bond Guarantee program, and the Canadian picture. It belongs to our contract surety guide, which covers bid, performance and payment bonds themselves.
A surety bond has three parties: the contractor (principal), the owner or prime contractor that requires the bond (obligee), and the surety that guarantees the contractor's promise. Our surety 101 guide covers that structure in general. What matters here is how the surety decides whether to sign.
Both main North American associations describe it the same way. The National Association of Surety Bond Producers (NASBP) says: "Obtaining bonds is more like obtaining bank credit than purchasing insurance." The Surety Association of Canada (Surety Canada) puts it the same way, adding: "Like your bank, a surety company wants to know you well before committing its assets."
The surety expects to be repaid: if it pays a claim, it looks to the contractor and other indemnitors for reimbursement. So underwriting aims to avoid losses by picking contractors that will finish their jobs and pay their bills, and by keeping each one's workload within what it can carry. That's why capacity is specific to each contractor and each surety.
Surety underwriting is often summarized as the "three Cs." The Surety & Fidelity Association of America (SFAA) teaches them in its contractor education modules: "During the traditional underwriting process, most sureties evaluate the three C's: Character, Capacity and Capital. Character is the most important of the three C's."
| C | The underwriter's question | What usually supports the answer |
|---|---|---|
| Character | Will the owners keep their promises when a job goes wrong? | Track record, references, credit history, how past disputes were handled |
| Capacity | Can the firm actually do this work, at this size, alongside everything else it has on? | Experience on similar jobs, key people, equipment, systems, current workload, continuity plans |
| Capital | Can the balance sheet absorb losses, slow payments and cost overruns? | CPA-prepared financial statements, working capital, net worth, bank line, profit history |
US federal rules use a closely related formula. Under the SBA's regulations, "Sureties must evaluate the credit, capacity, and character of a Principal using standards generally accepted by the surety industry" (13 CFR 115.15(a)(1)).
The three Cs are a summary, not a checklist. A 2021 article in NASBP's Surety Bond Quarterly noted that the phrase "falls short of describing the true extent of the robust and complex set of processes" that sureties use. Underwriters also look at related companies, owners' personal finances and contract terms.
Not every bond gets a full review. SFAA describes two paths:
Surety Canada warns that a first prequalification "takes time - sometimes weeks - to develop and present data, address questions the surety may have, and verify information." NASBP adds: "In no event should a bid be submitted for a bonded project before surety arrangements are in place."
Requirements vary by surety, but the NASBP and Surety Canada guides list a common core.
The company and its people
Track record and workload
Financial information
Owners and related companies
NASBP says the surety "will request fiscal year-end statements for at least the past three years and may require a financial statement audited by a certified public accountant (CPA)." Surety Canada says "the last three to five years." The 2021 Surety Bond Quarterly article adds that "Every related entity needs to be reported, as well as any intercompany receivables associated with those entities."
The accountant's report at the front of the statements tells the surety how much an outside CPA has checked. NASBP describes this as the "Accountant's opinion page—discloses whether the statements were prepared according to audit, review, or compilation standards." There are three levels.
| Level | What the CPA does | Assurance |
|---|---|---|
| Compilation | Presents management's numbers in financial statement form without verifying them | None |
| Review | Inquiries and analytical procedures | Limited |
| Audit | Tests records and verifies items with outside sources | Highest (reasonable assurance) |
In the US, a review follows AICPA standard AR-C section 90, whose objective is "to obtain limited assurance, primarily by performing analytical procedures and inquiries." NASBP calls the review "the most commonly used" level.
In Canada, compilations follow Canadian Standard on Related Services (CSRS) 4200. Ontario's public accounting regulation requires a "Compilation Engagement Report" for compiled financial information for periods ending on or after December 14, 2021, replacing the older "Notice to Reader." The prescribed report says the accountant does "not express an audit opinion or a review conclusion, or provide any form of assurance on the financial information" (O. Reg. 324/21, s. 4).
What sureties say about each level. NASBP: "A compilation, however, provides little or no assurance of the credibility of the figures presented and would typically be accepted only for interim statements," and "While sureties may offer modest programs based on review or compilation statements, audited financial statements are most often required, especially for larger work programs." Surety Canada: "Sureties prefer audited fiscal year-end statements, but there are occasions when a surety may accept a review statement," and "Many sureties will insist that at least the most recent fiscal year-end statements be prepared to full audit standards."
No public source we checked sets a dollar threshold at which a surety moves from review to audit. That is each surety's call.
Licensing boards sometimes do, and those rules are easy to confuse with surety practice. Tennessee's licensing board, for example, requires a "Reviewed" statement for monetary limits of $3,000,000 or less and an "Audited" statement above that, and calculates a license's per-project limit as "10 times the lesser of working capital or net worth, plus required experience." Those are licensing rules, not a surety's capacity formula. Our guide to Tennessee's contractor financial statement and surety bond option explains them.
For a contractor, the income statement is the sum of its jobs. The WIP schedule shows the jobs. NASBP says contractors "need to prepare a quarterly schedule of work in progress," listing each job with:
These schedules "should tie into the balance sheet," NASBP says. The 2021 Surety Bond Quarterly article explains what underwriters do with them: they "continually track WIP and compile a completed contract schedule that compares projected financials to actuals, in an attempt to identify any profit fade or other trends," and "keep a watchful eye for under-billings."
Profit fade means a job's expected margin shrinks quarter after quarter. Under-billings mean costs and estimated earnings run ahead of billings, which can point to unapproved change orders or unrecognized overruns.
Accounting method matters too. NASBP says the AICPA's construction contractor guide "recommends the percentage-of-completion accounting method, which is also preferred by most sureties."
Construction is cash-hungry. NASBP's "51 Questions" guide says contractors need enough cash and working capital "to upfront the costs for insurance, bonding, labor, materials, and overhead for 60 to 90 days until they receive the first payment certification from the owner."
Two balance sheet measures come up in every underwriting conversation:
NASBP also ties them to capacity directly: "The higher the working capital and net worth, the higher the bonding capacity will be." The same guide gives one rough benchmark: "Sureties typically require roughly 10% of the requested bonding program in working capital." That's NASBP's general description, in a guide carrying a 2016 copyright. It is not a formula that any particular surety uses, and individual sureties weigh many other factors.
The bank line of credit backs up working capital. NASBP lists "Evidence of a bank line of credit to augment working capital and to handle temporary cash flow deficits or strains," and says sureties "will look at the security for the credit and the extent to which bank loans are used and the amount and terms of their repayment."
Before bonds are issued, the surety will ask for a general indemnity agreement (GIA). NASBP describes it as obligating "the named indemnitors to protect the surety company from any loss or expense incurred by the surety on behalf of the contractor."
Who signs is part of underwriting. NASBP says a surety "almost always requires that the principal, the individuals who own and/or control the company, their spouses, and often affiliated companies sign the GIA." Surety Canada says the indemnity "will be required of the contracting firm and may also be required of the firm's owners and their spouses."
The wording isn't standard. NASBP cautions that "there is no standard indemnity agreement and that the language of GIAs varies from surety to surety," and recommends legal advice before signing. GIAs often include collateral and information rights that matter if a claim arises. Our guide to personal guaranties alongside surety indemnity shows how far those promises can reach.
Once a surety is satisfied, it sets a program. Surety Canada describes the document: the surety will "formalize the arrangement by providing you and your broker with a program authorization letter," which typically includes:
The single-job limit caps the size of any one contract the surety will bond under the program. It reflects whether the firm has done jobs of that size and type, and how much one bad job could hurt its balance sheet.
The aggregate limit caps total work on hand: the uncompleted value of all contracts. Both NASBP and Surety Canada say sureties want "the single job size and aggregate workload" including all projects, "bonded or not."
Why unbonded work counts. NASBP explains that sureties "include both bonded and unbonded projects in their analysis and calculation of a contractor's bond program because both kinds of projects require working capital and use resources." Outstanding bids count too, because "pending bids/proposals must be considered by the surety in evaluating the overall credit risk profile."
The SBA's rules show the same structure. An SBA "surety bonding line" under 13 CFR 115.33 limits, among other things, its term ("not to exceed 1 year subject to renewal in writing"), "The total dollar amount of the Principal's bonded and unbonded work on hand at any time, including outstanding bids," and "The maximum dollar amount of any single guaranteed bonded Contract."
A limit is not a promise. Surety Canada notes that the underwriter "will examine each request and review the terms and conditions of the contract documents and bond forms. If they are found unacceptable, the surety may decline to write the bond even though the other underwriting factors are favorable." A job that exceeds either limit, or is outside the firm's usual work, goes back to the underwriter for a separate decision.
Capacity has a second ceiling: the surety's own. On US federal work, a surety must be listed in Treasury Department Circular 570, which the Bureau of the Fiscal Service says "was updated on August 1, 2026."
Federal rules cap how much any one listed company may take on a single bond. Under 31 CFR 223.10(a), a company may not underwrite any single risk greater than "10 percent of the paid-up capital and surplus of such company, as determined by Treasury," a figure called "the underwriting limitation." Circular 570 lists each company's figure.
Larger bonds are handled by sharing the risk. 31 CFR 223.11(a) allows coinsurance, where two or more companies "underwrite a single risk on any bond or policy, the amount of which does not exceed their aggregate underwriting limitations," and the rules also allow reinsurance. Federal Acquisition Regulation (FAR) 28.202(a)(2) says a bond's penal amount "should not exceed the surety's underwriting limit stated in the Treasury Department Circular 570," and that a larger bond is acceptable only if the excess "is coinsured or reinsured."
These limits bind the surety, not the contractor, whose program depends on its own finances.
Capacity isn't fixed. Surety Canada: "After the bonds are written, the surety will continuously re-evaluate the overall performance and financial position of the contractor. Adverse changes may cause the surety to reduce or terminate the bonding program, while positive results may serve as the basis for an increase in the available bonding capacity."
What tends to help, according to the association guides:
What tends to hurt: losses, profit fade, unexplained under-billings, late statements, and backlog growing faster than capital.
In the US, a small contractor that doesn't yet meet a surety's standard criteria may qualify through the SBA's Surety Bond Guarantee program. The SBA says it guarantees bonds "for certain surety companies, which allows the companies to offer surety bonds to small businesses that might not meet the criteria for other sureties." Our SBA Surety Bond Guarantee guide covers the program in depth; here are the points that matter for capacity, checked October 23, 2026.
| Feature | What the SBA page and 13 CFR Part 115 say |
|---|---|
| Bonds covered | Bid, payment, performance and ancillary bonds on contracts. SBA "doesn't guarantee commercial bonds." |
| Contract size | "Up to $9 million for non-federal contracts and up to $14 million for federal contracts." The rule sets $9 million "as adjusted for inflation," and $14 million where a federal contracting officer certifies the guarantee "is necessary" (13 CFR 115.10, 115.12(e)(3)). |
| Underwriting | The applicant must "Meet the surety company's credit, capacity, and character requirements." |
| Guarantee share (Prior Approval sureties) | 90% of the loss on contracts of $100,000 or less, and for businesses owned and controlled by socially and economically disadvantaged individuals, HUBZone firms, and veteran- and service-disabled-veteran-owned firms; otherwise up to 80% (13 CFR 115.31). |
| Fee | SBA's surety bonds page says small businesses pay "a fee of 0.6% of the contract price" for performance and payment bond guarantees, and SBA charges no fee for bid bond guarantees. For Prior Approval guarantees approved on or after November 30, 2026, the contractor fee rises to $7.29 per $1,000 of contract amount, except on manufacturing (NAICS 31–33) projects (91 FR 68580). |
| Quick Bond | A streamlined application "used only for contract amounts that do not exceed $500,000 at the time of application" (13 CFR 115.30). |
The guarantee doesn't replace underwriting. The surety still decides, and the contractor still signs an indemnity. What changes is the surety's risk: with part of any loss guaranteed, it can bond firms it otherwise might not, and completed guaranteed jobs build a track record.
The fundamentals are the same in Canada, and Surety Canada's contractor guide reads much like NASBP's. A few points differ in practice:
We found no Canadian federal equivalent of the SBA guarantee program in the public sources checked for this guide.
What is bonding capacity? It is a surety's judgment of how much contract work a contractor can carry, usually expressed as a single-job limit and an aggregate limit on total work on hand. It is set by underwriting, not by a published table.
What is the difference between a single-job limit and an aggregate limit? The single-job limit caps the size of any one bonded contract. The aggregate limit caps the total uncompleted value of all work, which sureties measure including unbonded work and often outstanding bids.
Do I need audited financial statements to get bonded? Not always. NASBP and Surety Canada say sureties may accept reviewed statements, and sometimes compilations, for modest programs, but generally prefer audits and often require them for larger programs.
Can the SBA help a new contractor get bonded? In the US, the SBA guarantees bid, payment, performance and ancillary bonds for eligible small businesses on contracts up to $9 million, or $14 million for certain federal contracts. The applicant still has to meet the surety's credit, capacity and character requirements.
Retrieved or confirmed October 23, 2026 (PT); Source 17 October 30, 2026.
