An employer has just told you that your tender, or your contract award, is conditional upon providing a surety bond.
Maybe it’s a specific figure like 10% of contract value or maybe the tender documents just say, ‘surety bond required’ and leave you to work out the rest.
If you’ve not dealt with one before, the first questions are usually the same:
What exactly is this? Is it the same as insurance? Will it tie up my overdraft or credit facilities? And which type do I need?
This guide answers all of that in plain terms, so you know what you’re looking at before you go to a broker or surety provider.
Surety Bond vs Insurance: They’re Not the Same Thing
This is where most confusion starts, because bonds are often bought through insurance brokers and look, on paper, like an insurance product.
They aren’t the same, and the distinction matters. Here’s the difference:
Insurance protects against an uncertain event. It protects your project against something that may or may not happen, like fire, theft, or accidental damage. The insurer prices the risk and expects to pay claims across its book.
A surety bond is a guarantee of performance:
The underlying assumption is that the contractor will deliver – the surety is underwriting the contractor’s ability and track record to do so, not betting against the possibility or probability of misfortune.
If a claim is paid, the surety or guarantor typically has the right to recover that cost from the contractor, because the contractor was expected to perform all along. That’s a fundamentally different relationship than the one you have with your public liability or contract works insurer.
The Main Types of Bonds
Not every bond does the same job. Which one you’re asked for depends on the stage of the project and what the employer is trying to protect against. Here are the three most popular surety bond types in the UK:
A Performance Bond
This is the most common bond in UK construction. It guarantees that the contractor will carry out the contract in accordance with its terms – if they don’t, the employer can call on the bond to cover the cost of completing or remedying the work, usually up to a set percentage of contract value (commonly 10%). Most main contracts and many subcontracts require one before work starts.
There are various performance bond types like: on-demand bonds, conditional bonds and retention bonds. For a deeper look at how these work and how they’re priced, see our performance bonds guide.
An Advance Payment Bond
Where an employer pays a contractor money up front – for mobilisation, materials, or early-stage costs – guarantees that money back if the contractor fails to deliver the work it was paid for. It protects the employer’s cash flow position on the advance, not the whole contract. Advance payment bonds are widely used across construction projects, infrastructure works and specialist supply contracts where early funding is required but financial risk must remain controlled.
A Bid Bond
Used at tender stage, a bid bond guarantees that if a contractor wins the tender, they’ll sign the contract and provide any further bonds required (like a performance bond).
It protects the employer from tenderers who submit a bid and then withdraw or fail to proceed, which would otherwise cost time and money to re-tender.
A Road and Sewer Bond
Required by local authorities under Section 38 or Section 104 agreements, it guarantees that new roads and sewers built as part of a development will be completed to adoptable standard, so the authority isn’t left to fund unfinished infrastructure.
It’s a fixture of most residential and mixed-use developments. Our road and sewer bonds page covers the process and typical costs in detail.
Surety Bond vs Bank Guarantee: The Working Capital Difference
Contractors sometimes assume a bank guarantee is the only option, but it comes with a real cost most people don’t fully account for until they’re mid-negotiation with their bank.
A bank guarantee typically requires cash collateral or draws directly against your existing credit facilities. That’s working capital locked away and unavailable for materials, payroll or the next tender.
A surety bond, by contrast, is underwritten against the contractor’s financial standing and track record rather than secured against your bank lines.
It doesn’t tie up credit facilities in the same way, which means the capital stays available for running the business rather than sitting behind a guarantee. For contractors juggling several live contracts at once, this is often the deciding factor between the two routes.
Getting the Right Bond in Place
The type of bond you need comes down to what stage you’re at and what the contract or planning condition specifies. If you’re still working out which bond applies to your project – or want to understand how performance bonds and road and sewer bonds are assessed and priced – our dedicated pages go into the detail for each.
Read our construction surety hub for an overview of all bond types, or go straight to the guide relevant to your situation.
You can contact us at +443331508571 to speak to a specialist or get a quote.
