Your building contract requires a bank guarantee: Could an insurance bond preserve your cash?
Bank guarantees for builders can tie up working cash, while an accepted insurer-issued performance bond may preserve money needed to deliver the build.
Winning a building contract ought to be a good moment. There are trades to book, materials to order and a site programme to get moving.
Then the client asks for a bank guarantee.
If arranging it means setting aside a large cash deposit, the job can start looking less comfortable before anyone arrives on site. The money intended for wages and suppliers now has another purpose.
For an Australian building business, that is where an insurer-issued performance bond may be worth investigating. The opportunity is to meet the client's security requirement while tying up less cash. Whether it works depends on the contract, the client's acceptance and the terms offered to the builder.
The short answer
Contract performance security gives the client financial protection under the agreed terms.
The guarantee amount and the cash backing it are separate figures.
A 5% requirement must be read against the actual building contract.
An accepted insurer-issued bond may require less cash upfront.
Fees, backing, reimbursement obligations and release conditions still matter.
Bank guarantees for builders: Why the client wants one
The client commissioning the build wants some financial protection if the work goes wrong. A bank guarantee is a bank-issued undertaking to pay the client an agreed amount when the instrument's demand requirements are met.
In the building contract, the client may be called the principal and the builder the contractor.
Performance security is the broad purpose. Performance bond is also a broad term: the ATO explains that it can include bank guarantees and insurance bonds, depending on the issuer. Here, an insurance bond means an insurer-issued performance bond offered as an alternative to a bank-issued guarantee. The actual wording governs what each instrument promises.
The Commonwealth's financial-viability guidance describes bank guarantees and insurance bonds as forms of performance security. Although its setting is government procurement, the distinction is useful: the assurance is provided to the party purchasing the work.
Issuing a $100,000 guarantee does not put $100,000 into the builder's trading account. The business still needs money to build.
It is also separate from borrowing against a property or arranging a construction loan. Keeping those ideas apart helps explain why a security requirement can affect cash flow without itself providing funding. The guide to working capital for a new contract examines the delivery costs that sit alongside it.
Where the 5% comes from
Imagine a $2 million building contract that expressly requires security equal to 5% of the contract price. The required guarantee would be $100,000.
That is the assumption in this example, not a universal rule.
The percentage, calculation basis and acceptable form depend on the contract and applicable law. GST, variations and later reductions may affect the calculation, so the wording needs to be checked rather than copied from another job.
This contractual amount is different from a deposit on a loan facility or a lender's required contribution to a property purchase or development.
Before the programme and cash budget are finalised, your solicitor can identify what the contract requires, who receives the guarantee and when it must be delivered. Discovering those details after the money has been committed elsewhere can leave the builder with an avoidable squeeze.
When money in the account stops being money for the build
Suppose the issuer requires the full $100,000 as cash backing for the guarantee. The client holds the instrument, while the supporting money is restricted under the issuer's arrangement.
The account may still show the cash. The site team cannot spend it on materials.
Other proposals may involve different security or capacity within an existing facility. That makes the written terms important, including the effect on other borrowing. The multiple business loans checklist helps bring those connections into view.
NSW Treasury's construction-security guidance recognises that quarantined cash can reduce a contractor's working capital. It also notes that insurance bonds are not typically backed by a cash deposit. That guidance concerns NSW government projects and does not override a private building contract.
Could an insurer-issued performance bond leave more cash available?
An insurer-issued performance bond may provide an undertaking the client accepts in place of a bank guarantee. If it requires less cash backing, more of the builder's money can remain available for the work.
The client has to accept the arrangement, and the builder has to qualify for it.
Neither should be taken for granted. The issuer, wording and contractual position need to be settled before the business relies on the substitution. For NSW government work, the current guarantee-acceptance policy, TPG25-14, effective from January 2026, includes issuer-eligibility requirements. Private clients have their own contractual position.
A suitably qualified insurance or surety adviser can assess the proposed bond. Your finance broker can help consider what its cash requirements mean alongside the business's other funding. An approval, zero collateral or a lower total cost cannot be assumed from the product's name.
The insurer's involvement does not make the builder's exposure disappear
It is easy to hear the word insurance and assume that a payment under the bond becomes someone else's problem.
The documents may tell a different story.
The builder may have reimbursement obligations if the issuer pays, supported by company indemnities, personal guarantees or other security. An indemnity can create an obligation to repay an amount paid under the bond. Your solicitor should explain the actual exposure before the arrangement is accepted.
The ATO's explanation of guarantees and performance bonds discusses these arrangements and reimbursement risk. It provides background, rather than transaction-specific tax advice.
Quoted premiums, fees, extensions and any collateral belong in the comparison. Less cash tied up at the start can help liquidity while a substantial obligation remains if the bond is called.
The same $100,000 security, two different cash positions
Consider an original hypothetical building company with $300,000 of unrestricted cash. Its new $2 million contract requires the $100,000 security described earlier.
Assume the next phase of site costs, wages and supplier payments needs $180,000 before the next client receipt.
With a fully cash-backed guarantee, $200,000 remains available before those project payments. After them, the builder has $20,000, before guarantee fees and any other commitments excluded from this example.
Now assume an insurer approves a $100,000 performance bond, the client accepts it and no cash collateral is required. The builder retains $300,000 before fees and has $120,000 after the same project payments. The insurance bond costs must then be deducted.
The difference is cash that has not been tied up. No new loan has been advanced and the contract has not become more profitable.
These assumptions illustrate the mechanics, not an offer or approval. The working-capital needs guide helps examine whether either remaining balance would cover the rest of the company's commitments.
The release date deserves as much attention as the issue date
An insurance bond that preserves cash at the start still needs to be managed through the build. Delays may bring extension costs or replacement requirements. Practical completion does not necessarily end every security obligation that day.
The actual reduction and release conditions need a place in the project timetable.
If cash backs an existing bank guarantee, replacing it with an insurance bond does not automatically release that money. The client's acceptance, cancellation of the old instrument and release of the supporting cash need to be coordinated. The guide to cash reserves and unused credit lines explains why a possible future release is different from cash available today.
A 13-week cash-flow forecast can show whether the proposed timing helps the next payroll or supplier run. Keeping a register across active jobs also makes it harder to overlook security still outstanding on an earlier build.
Frequently asked questions
Is an insurer-issued performance bond a loan to the builder?
No. It provides security to the client. It may preserve cash that would otherwise be restricted, but it does not itself advance working capital.
Does every building contract require 5% security?
No. The 5% calculation above is illustrative. The actual contract and applicable law determine the requirement, rather than a national rule or standard loan contribution.
Can I insist that the client accepts an insurance bond?
Do not assume so. Acceptance depends on the contract, applicable law, issuer and wording. Establish the position before relying on a substitution.
What if the client calls the guarantee or bond?
The issuer may pay under the instrument's terms. Reimbursement obligations and rights under the building contract need separate legal review. A dispute does not necessarily stop payment under an on-demand instrument.
Leave room for the work you have won
The security is one part of winning the job. Understanding what each acceptable option costs, ties up and could leave owing helps keep attention on the other part: having enough cash to deliver the build.
Planning Cash Flow for Your Next Building Contract?
Fairlane Finance can help you assess the cash needed to deliver the build alongside its security requirements.
General information only. This article does not constitute financial, credit, legal, tax, accounting, compliance or valuation advice. Finance is subject to lender approval, eligibility criteria, terms, fees and conditions. Consider obtaining independent professional advice for your circumstances before acting.
