Surety Bond Cost Calculator

What you are actually buying

A surety bond is not insurance for you. Insurance protects the person who buys it; a surety bond protects somebody else — the project owner — against your failure to perform. If the surety pays a claim, it comes after you for every dollar, because you signed a general indemnity agreement when you took the bond out. That indemnity usually reaches your personal assets and often your spouse's.

So the premium is not a risk-transfer price the way an insurance premium is. It is closer to a credit fee: the surety is extending credit on your behalf and charging for the exposure.

Premium = bond amount × rate

For a well-qualified contractor the rate runs 1 to 3% of the bond amount. On a $500,000 performance and payment bond that is $5,000 to $15,000. Below that tier it climbs steeply — 5 to 10% is common through specialty or "credit-challenged" markets, and at the bottom you may be asked to post collateral for part of the penal sum on top of paying the premium.

The four bond types, plainly

This is where most of the confusion sits, and the names do not help.

Bid bond. Guarantees that if you win, you will actually sign the contract at the price you bid and provide the performance bond. Usually 5 or 10% of the bid. Often issued at a small flat fee, or free, by the surety that expects to write the performance bond — they are effectively pre-qualifying you. If you win and then walk away, the bond pays the owner the difference between your bid and the next one.

Performance bond. Guarantees the work gets completed to the contract. If you default, the surety can finance you through, tender a replacement contractor, or pay the owner up to the penal sum. Almost always 100% of the contract value on public work.

Payment bond. Guarantees your subcontractors and suppliers get paid. It exists because you cannot place a mechanic's lien on public property, so this bond is the substitute remedy. Nearly always issued alongside the performance bond and priced together, which is why the combined option here costs a little more than performance alone rather than double.

Licence or permit bond. A small bond a state or municipality requires before it will issue you a contractor licence — often $10,000 to $25,000 — guaranteeing you will comply with the licensing statute. These are annual, cheap, and usually written off a credit check alone with no financial statements.

Bid, performance and payment are contract surety. Licence is commercial surety. Different underwriters, different files, different pricing logic.

What underwriting is really looking at

Contractors assume the surety is assessing the project. It is mostly assessing them. The classic frame is the three Cs:

• Capital — working capital and net worth. The rough benchmark is working capital of 10% of the largest bonded job and 5% of total backlog. Miss it and you either pay more or get declined.
• Capacity — have you completed jobs of this size and type before? A roofer who has never run a job above $200,000 asking to bond a $2 million contract is a hard file regardless of credit, because the failure mode is well documented: the biggest job a contractor ever takes is frequently the last one.
• Character — credit score, payment history with suppliers, litigation, tax liens, and whether your accounting is any good. CPA-reviewed statements price better than internally prepared ones; audited statements better still.

Single-job capacity is commonly extended at around ten times working capital, with aggregate programme capacity around twenty times. That is the constraint that actually limits which jobs you can chase, more than the premium does.

A worked example

A carpentry contractor with $3 million revenue, six years in business, good credit and $250,000 working capital bidding a $500,000 job needing performance and payment bonds:

• Base rate for the good tier: 1.5% to 2.5%
• Combined performance and payment factor: 1.15
• Six years trading: 1.0
• Job is 17% of annual revenue: 1.0
• Working capital $250,000 against a $50,000 benchmark, a 5.0 ratio: 0.9
• Adjusted rate: 1.5% × 1.035 to 2.5% × 1.035 = 1.55% to 2.59%
• Premium: roughly $7,800 to $12,900

Drop the working capital to $30,000 and the factor becomes 1.5, pushing the premium past $21,000 — for exactly the same job. The balance sheet moves the price far more than the project does.

Practical notes

Put the premium in the bid as a line item. It is a direct project cost, not overhead, and on public work everybody bidding is carrying it.

Start the surety relationship before you need it. Getting bonded for the first time takes weeks: financial statements, a work-in-progress schedule, bank references, personal financial statements from every owner, and the indemnity agreement. Turning up three days before a bid deadline having never spoken to an agent is how contractors miss bids.

Use a surety-specialist agent rather than your general insurance broker. Sureties have appetites — this one likes site work, that one will not touch residential — and an agent who places bonds every day knows which market to take your file to. It costs you nothing extra; the commission is inside the premium either way.

If you are small, new, or repairing credit, look at the SBA Surety Bond Guarantee programme. The SBA guarantees a share of the surety's loss on bonds up to $6.5 million, which brings underwriters to files they would otherwise decline.