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Delivery risk only · Often the lowest-rated contract bond

Supply Bond CalculatorDerive the Penal Sum, Then Price It

Supply bond math is a two-step problem, and step one is the part that trips suppliers up. No statute fixes a supply bond amount the way the Miller Act fixes construction bonds at 100% of contract price — on federal supply work the contracting officer sets the penal sum, and state and private obligees write their own figure into the bond clause. This calculator derives the bond amount from your contract value and contract type, then prices it on the same sliding scale our performance bond calculator uses — where supply bonds typically land at the favorable end, roughly 1-3% of the bond amount.

The federal rules come from FAR 28.103, not the Miller Act — a distinction that decides whether your contract needs a bond at all (most federal supply awards do not). When the answer comes back as a bonded contract, you can start a supply bond quote with the numbers this page produces, or browse the rest of the bond calculator hub if your contract also carries installation scope.

Run the Two-Step Math

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The full price of the goods, materials, or equipment under contract — not the bond amount. The calculator derives that next.

Contract Type

Leave at 100% unless your solicitation states a lower penal sum (e.g., sized to progress payments).

Owner's personal FICO band. Financials matter more as contracts grow.

Get the firm number

An underwriter reads your actual bond clause, confirms the penal sum the obligee requires, and quotes off that number — not an assumption.

Step 1: No Statute Sets Your Supply Bond Amount — the Contract Does

A calculator that opens by asking for a bond amount assumes a number you may not know yet. For supply contracts, the penal sum comes from the bond clause in your solicitation, and how it gets there depends on who the obligee is.

Federal

CO-determined

Under FAR 28.103-2 the contracting officer sets an amount adequate to protect the government's interest — commonly the full contract value, sometimes sized to progress-payment exposure. Bond paper is SF 1418 (performance) / SF 1416 (payment) under FAR 52.228-16.

State / Municipal

Solicitation-set

Public buyers below the federal level write the penal sum into the bid documents — in practice commonly 100% of contract price for goods the institution depends on: fuel, food service commodities, fleet vehicles, long-lead equipment.

Private / GC-Required

Negotiated

A general contractor on a bonded project may require critical material suppliers to post supply bonds so a supplier default cannot cascade into a claim on the GC's own performance bond. Often 100% of the supply package; partial amounts are negotiable.

Before You Price It: Does Your Federal Supply Contract Even Need a Bond?

For federal suppliers, the question before the calculator is whether a bond applies at all — and the default answer is no. The Miller Act covers construction, alteration, and repair of public works; goods-only contracts are governed by FAR 28.103, which starts from the opposite presumption.

Official Federal (FAR Part 28, non-construction) Requirements

"Generally, agencies shall not require performance and payment bonds for other than construction contracts."
Federal Acquisition Regulation • FAR 28.103-1(a)

The exception lives in FAR 28.103-2: above the simplified acquisition threshold (currently $250,000), a contracting officer may require a performance bond when necessary to protect the government's interest. The regulation enumerates the situations that justify it:

Government property or funds in your hands

Government-furnished material, tooling, or advanced funds put federal assets at risk inside your operation — the lead trigger for a bonded supply contract, and often the one that sizes the penal sum.

Substantial progress payments before delivery

If the government pays a large share of the price before end items start shipping, it carries delivery risk on money already out the door — a bond backs that exposure.

Asset sale, merger, or novation mid-contract

A contractor selling out or merging while holding government contracts raises the question of who will actually perform — FAR 28.103-2 flags it as grounds for requiring a bond.

Dismantling, demolition, or removal work

Contracts for dismantling or removal of improvements sit in the non-construction bucket but carry physical risk to government property — another enumerated trigger.

Manufacturers: the same rules, a deeper dive

FAR 28.103-2 also permits additional bond protection when a contract price is increased, and a payment bond can only attach (under 28.103-3) where a performance bond is already required. If you manufacture end items for federal buyers rather than distribute them, the manufacturing performance bond guide walks the full FAR Part 28 analysis, and the government contracts bond page covers the broader federal bonding landscape.

Step 2: The Premium — Sliding Scale First, Credit Tier Second

Once the bond amount is fixed, supply bonds price like any contract bond: a size-based base rate, adjusted by the account's credit and financial strength. Bigger bond amounts earn lower percentage rates because underwriting costs are largely fixed per bond. Supply obligations then get one structural break — the underwriter is pricing whether you can source and ship goods, not whether a job site stays on schedule, which is why clean supply accounts often quote at or below the low end of each band shown here.

What pulls your rate toward the low end

  • Goods you stock or source routinely — distributors with established supplier relationships underwrite faster than custom fabricators.
  • Business financials that show the working capital to fund the order before payment — the supply-side equivalent of a contractor's WIP schedule.
  • A penal sum below full contract value (progress-payment sizing) — the rate applies to the bond amount, so a smaller bond is cheaper twice over.

What pushes it up

  • Volatile commodity pricing — a supplier underwater on a fixed-price contract is the classic supply bond claim scenario.
  • Single-source or long-lead items with no substitute supplier if you fail.
  • Personal credit below 670 — though bad credit bond programs place supply obligations more readily than construction risk for the same applicant.

Three Worked Supply Bond Estimates

Same two-step method the calculator runs, applied to three contracts a supplier actually sees. All three assume standard credit (700-739, 1.0x multiplier); move one tier in either direction and scale the premium by the multipliers above.

ScenarioContract ValueStep 1: Bond AmountBase Rate BandStep 2: Premium
Federal supply awardCO requires bond at full value (government-furnished material on site)$400,000$400,000 (100%)1%–2%$4,000–$8,000
Federal, progress-payment sizing$2M contract; penal sum set to the $600K progress-payment exposure$2,000,000$600,000 (30%)0.75%–1.5%$4,500–$9,000
GC-required private supply bondStructural steel package on a bonded commercial project, full value$150,000$150,000 (100%)1%–2%$1,500–$3,000

Estimates, not quotes. The middle row is the scenario suppliers miss most often: when the bond exists because of progress payments, the penal sum is sometimes sized to that exposure rather than the contract price — which cut this premium roughly in half versus a full-value bond. Always quote off the exact penal sum in your bond clause.

Quote Your Actual Bond Clause

Supply Bond Premium vs Performance Bond Premium

Both bonds run through the same sliding scale, so why does the supply bond usually cost less for the same dollar figure? Because the bond amounts are derived differently and the risk being priced is narrower. Use the comparison to pick the right calculator — if your contract includes installation labor, you are pricing a performance bond, not a supply bond.

Supply bond

  • Guarantees: the goods arrive — on time, to spec, at the contract price. No labor, no installation.
  • Bond amount: set by the contract clause; no statutory formula. Commonly 100% of contract value, sometimes sized to progress payments.
  • Federal basis: discretionary under FAR 28.103 — the exception, not the rule. SF 1418 / SF 1416 forms.
  • Typical pricing: roughly 1-3% of the bond amount, often the lowest-rated of the contract bonds. Full product detail on the supply bonds page.

Performance bond

  • Guarantees: completed work — labor, materials, schedule, and workmanship together.
  • Bond amount: fixed at 100% of contract price on federal construction over $150,000 (FAR 28.102-2); state little Miller Acts track the same model.
  • Federal basis: mandatory under the Miller Act (40 U.S.C. 3131) for construction, alteration, and repair. SF 25 / SF 25-A forms.
  • Typical pricing: 0.5%-3% of contract price by size and credit — run it on the performance bond calculator or see the performance bond cost guide.

Hybrid furnish-and-install contracts get treated as performance risk — the labor component controls. And where a federal supply contract does carry a payment bond, it only attaches alongside a required performance bond (FAR 28.103-3), the same pairing logic behind performance and payment bonds on construction work. For the broader category, the contract bonds hub maps every instrument in the family, and surety bond cost covers the rate drivers common to all of them.

Bond clause due back with your bid?

Supply obligations underwrite fast — no WIP schedule, no job-site review. Send the solicitation's bond language and contract value, and our desk confirms the penal sum and quotes the same day for most accounts. Call 1-844-810-BOND (2663) or start online.

Get Supply Bond QuoteCall Underwriting

If Your Contract Carries More Than Delivery Risk

Furnish-and-install scope, public bidding, or a full bonded program — each has its own math.

Performance Bond Calculator

Your contract includes installation or construction labor. Bond amount is 100% of contract price on public work; credit-tier sliding-scale pricing.

Run the math

Payment Bond Calculator

On bonded supply contracts a payment bond can pair with the performance bond (FAR 28.103-3) to protect your own sub-suppliers.

Run the math

Bid Bond Calculator

Bidding public supply work that requires bid security? Derive the penal sum from your bid and the solicitation percentage.

Run the math
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Supply Bond Calculator FAQs

The questions behind the inputs — penal sum sizing, federal forms, and where the rate actually comes from.

Why does the calculator default the bond amount to 100% of contract value?

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Because that is the most common sizing in practice — not because a statute requires it. Unlike federal construction, where FAR 28.102-2 fixes the performance bond at 100% of contract price above $150,000, no regulation sets a universal supply bond formula. On federal supply contracts the contracting officer determines an adequate penal sum under FAR 28.103-2, and state and private obligees write their own number into the bond clause — most often the full contract value, sometimes a percentage of it or an amount tied to progress payments. The calculator starts at 100% and lets you override it with the exact figure from your solicitation, which always controls.

Is a supply bond cheaper than a performance bond on the same contract value?

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Often, yes — for a structural underwriting reason. A construction performance bond prices labor productivity, subcontractor default, weather, and job-site risk on top of financial strength. A supply bond prices one question: can this business source and deliver the goods it sold? With the risk profile narrower, supply obligations tend to land toward the low end of the same sliding scale, and underwriters frequently approve supply applicants who would face friction on construction risk. The calculator uses the standard contract-surety rate schedule, so treat the low end of your result as the realistic landing zone for a clean supply account.

My federal solicitation references SF 1418 — what is it and does it change the math?

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Standard Form 1418 is the performance bond form for federal non-construction contracts (supplies and services), prescribed with FAR 52.228-16; SF 1416 is its payment bond counterpart. Construction contracts use different paper — SF 25 and SF 25-A under FAR 52.228-15. The form itself does not change your premium math, but it tells you which regime you are in: SF 1418 means the bond amount is whatever the contracting officer determined adequate, not the automatic 100%-of-contract figure the Miller Act imposes on construction. Pull the penal sum from the solicitation and enter that exact number in the calculator.

Does the $150,000 Miller Act threshold apply to my supply contract?

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No. The Miller Act (40 U.S.C. 3131) covers contracts for the construction, alteration, or repair of public buildings and public works — goods-only contracts sit entirely outside it, so its threshold is irrelevant to supply work. The gate that matters for suppliers is in FAR 28.103-2: a performance bond may be required on a non-construction contract exceeding the simplified acquisition threshold (currently $250,000) when the contracting officer finds it necessary to protect the government, citing triggers like government-furnished property, substantial progress payments before delivery, a mid-contract asset sale or merger, or dismantling work. Most federal supply awards require no bond at all.

Can the SBA guarantee program back a supply bond if my financials are thin?

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Yes. The SBA Surety Bond Guarantee Program guarantees bonds for eligible small businesses on contracts up to $9 million generally, and up to $14 million on federal contracts when the contracting officer certifies the guarantee is necessary — per current SBA program guidelines. The guarantee applies to contract bonds including supply obligations, and it is the standard route for suppliers whose working capital or credit would not clear a surety standard market on its own. Expect the surety to still review business financials; the SBA guarantee shifts risk, it does not skip underwriting.

What if the contracting officer sizes the bond to progress payments instead of the contract price?

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That happens, and it usually works in your favor. One of the FAR 28.103-2 triggers is substantial progress payments made before delivery of end items begins — when that is the reason for the bond, contracting officers sometimes size the penal sum to the government funds actually at risk rather than the full contract value. A $2 million supply contract with $600,000 of progress-payment exposure might carry a $600,000 bond, which cuts the premium roughly in proportion. Enter the stated penal sum as a custom bond percentage in the calculator (30% in that example) and the premium estimate adjusts automatically.

From Estimate to Issued Bond, Usually Same Day

Supply bonds are among the fastest contract bonds to place — the underwriting question is whether your business can source and deliver, not how a job site will run. Treasury-listed carriers, SF 1418/1416 federal paper accepted, and SBA Surety Bond Guarantee support available for small suppliers on contracts up to $9M ($14M federal).

Start Your Supply Bond Quote1-844-810-BOND
Eric Drummond, Licensed Surety Producer
Reviewed by
Eric Drummond, Licensed Surety Producer
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