Invoice Finance for Construction

The construction cash-flow reality: you do not raise ordinary invoices

Almost every guide to invoice finance assumes a simple picture: you deliver, you raise an invoice for a fixed sum, the customer owes that sum, and a funder advances against it. Construction does not work like that, and pretending it does is why so many subcontractors get declined or badly served.

A limited-company subcontractor rarely issues a plain sales invoice. On most commercial contracts you submit an application for payment (an AfP), stating the value of work done to date. The main contractor or a certifier then assesses it and issues a payment notice for a certified sum, which is often less than you applied for. They can serve a pay-less notice to reduce it further. Only then, and on the contract's payment terms (30, 45 or 60 days from the due date), does cash actually move. The debt is not certain when you apply for it, and it can be adjusted after the fact.

Stacked on top of that uncertainty are four features unique to this sector. Retention: the contractor holds back typically 3 to 5 percent of every payment as security against defects, releasing half at practical completion and the balance a year or more later. CIS: under the Construction Industry Scheme the contractor deducts 20 percent (or 30 percent if you are unregistered) from the labour element before paying you. Contra-charges: back-charges for remedial work, welfare, plant or damages are netted off what you actually receive. And main-contractor insolvency: if the firm above you fails, a certified debt can evaporate entirely. This is the working-capital reality invoice finance has to survive in construction, and it is a very different animal from a recruitment desk or a wholesale ledger.

Why standard factoring usually declines construction

Here is the honest fit verdict, and it is the whole point of this page: vanilla invoice factoring often excludes construction outright. Read the small print of many high-street factoring products and you will find a blanket construction exclusion. That is not the funder being difficult; it is a rational response to how construction debts behave.

Ordinary factoring is built on the assumption that a debt is certain, undisputed and payable in full on stated terms. Construction breaks all three assumptions. The sum is uncertified and adjustable, retention delays part of it for a year, CIS strips out a fifth of the labour value at source, contra-charges dilute what lands, pay-when-certified terms hand the timing to a third party, and contractor insolvency can cancel the debt. A generalist factor cannot underwrite that, so it says no.

What you need instead is a construction-specialist finance facility. These funders understand applications for payment, progress billing, certification and pay-less notices, retention, CIS and contra-charge dilution, and they price for it. Some run selective or single-contract facilities rather than whole-turnover lines, so you fund the contracts that suit and leave out the awkward ones. The mechanics of factoring and discounting in general are covered in our invoice finance guide; this page is about the construction-specific version and why the generalist version is the wrong door to knock on.

Factoring or discounting for a construction subcontractor?

The two familiar forms of invoice finance both exist in construction-specialist form, but the choice is shaped by the certification process rather than by preference alone.

Construction factoring means the funder advances against your certified applications and also handles collections, chasing the main contractor for payment. For a subcontractor with a lean back office and a handful of large main-contractor customers, outsourcing that chase is a genuine benefit. It is a disclosed arrangement: the contractor is notified to pay the funder. Because a small number of contractors usually dominate a subcontractor's ledger, this concentration is normal and specialist funders expect it, but it feeds into credit limits and advance rates.

Confidential construction discounting keeps you in control of your own applications and collections, with the contractor unaware a funder is involved. It suits larger, well-systemised subcontracting groups with strong financials, robust quantity-surveying and a proven record of clean certification. Because certification and dilution risk sit with you in a discounting facility, funders set the bar higher. For most growing subcontractor SMEs, a disclosed construction-factoring or selective facility is the realistic starting point. Compare the two mechanisms directly in our guides to invoice factoring and invoice discounting.

How much cash is really locked up? A worked example

Take a limited-company groundworks subcontractor on a single commercial contract worth £500,000, CIS-registered at the standard 20 percent rate, on 60-day payment terms from certification, with 5 percent retention. Assume a rough labour-to-materials split where the labour element attracts CIS.

Walk the cash through the construction machine and the trapped money becomes obvious.

Element	Amount	When you actually see it
Contract value	£500,000	Applied for in stages as work proceeds
Retention held (5%)	£25,000	Half at practical completion, half ~12 months later
Certified value payable through the job (95%)	£475,000	On 60-day terms after each certification
CIS deducted at source on the labour element (20%)	Deducted from each payment	Credited against your tax, not cash-in-hand now
Typical AfP-to-cash cycle	Certified value	Apply, certify, then 60 days to pay

The £25,000 retention sits unpaid for the length of the defects period, on a job whose net margin might be only a few percent, so a large slice of the profit on the contract is locked away for a year. On top of that, every certified application waits roughly two months from certification to payment, and the labour element arrives 20 percent lighter because of CIS deducted at source (recovered later through your CIS position, not as immediate cash). You are funding wages, plant hire, materials and your own overhead across that whole gap.

A construction-specialist facility advancing, say, 70 to 80 percent against the certified applications releases the bulk of that £475,000 within a day or two of each certification instead of 60 days later, which is what keeps the next stage of work moving. The retention is handled separately, either left to run or unlocked through a dedicated retention-release product. The funder models the net-of-CIS cash the contractor will actually pay, and prices for the certification and contra-charge risk that made a generalist factor walk away. For the detail of how retention and CIS deductions build up across your contracts, our trade colleagues cover it in the CIS retention payments guide and the CIS deduction rates guide.

Eligibility: what construction funders look for

Because the funding is secured against your certified applications rather than years of accounts, approval turns on the quality and structure of your contracts more than on your trading history. A construction-specialist funder assesses:

• Limited-company (or LLP) status, subcontracting to other businesses for business purposes. This is a company facility only.
• Certified, B2B applications: work billed to main contractors or commercial clients through AfPs or progress invoices, not cash retail or domestic work paid on completion.
• Main-contractor covenant: the financial strength of the firms above you, since they are the debtors. Strong, solvent main contractors support a higher advance rate.
• CIS position: registration status and, ideally, gross payment status, which removes the 20 percent deduction and improves both cash flow and the fundable sum.
• Clean contracts and certification history: clear contract terms, well-run quantity surveying, and a record of applications being certified close to applied value with few contra-charges.
• Turnover and contract mix: a real pipeline of certified work; selective facilities can fund single strong contracts even for younger companies.

What to watch: retention, CIS, contra-charges and insolvency

Retention. Standard facilities do not advance against retention, so do not assume the 3 to 5 percent held back is funded. If unlocking retention matters to you, ask specifically about a retention-release or retention-bond product, and read how it is priced.

CIS deductions. The 20 percent taken from your labour element at source reduces the cash a contractor pays, so it reduces what a funder can advance against. Gross payment status changes this materially: it lets the contractor pay you gross, improving both cash flow and your funding line. Whether you qualify is a tax-registration question, not a finance one.

Contra-charges and dilution. Back-charges for remedial work, welfare, plant hire or damages net off against your application and dilute what actually lands. A funder that advanced against the gross application is exposed when a contra-charge bites, so specialist lenders price for dilution and will scrutinise your history of disputes. Fewer contra-charges means better terms.

Main-contractor insolvency. This is the sector's defining risk. If the firm above you fails, a certified debt can be lost. On a recourse facility the funder can reclaim its advance, leaving your company to absorb the loss; a non-recourse or bad-debt-protected facility shifts some of that risk to the funder for a higher fee and within per-contractor credit limits. Construction insolvency is not rare, so understand exactly where the loss falls before you sign. Our trade colleagues track the pattern in their analysis of construction insolvency risk for subcontractors.

Pay-when-paid and pay-when-certified. Pay-when-paid clauses are largely unenforceable under the Housing Grants, Construction and Regeneration Act 1996 except on upstream insolvency, but long certification cycles and pay-when-certified terms are real and legal. A specialist funder underwrites this; a generalist cannot, which is the recurring theme of this page.

When invoice finance is the wrong tool for you

Invoice finance only helps where there is a certified B2B application to advance against. If your work is domestic and paid on completion (a jobbing builder invoicing homeowners), there is no main-contractor debtor to fund, and small domestic-facing firms are usually better served by a flexible working-capital line than by construction factoring. If your cash need is a one-off asset purchase (an excavator, a tipper, a welfare unit) rather than an ongoing payment gap, that is a job for hire purchase or leasing, not for a facility designed to bridge receivables.

And if you trade as a sole trader, this route is closed to you regardless (see the company-gate note below). For genuine cash-flow gaps outside the AfP cycle, a revolving credit facility you draw and repay as contracts ebb and flow, or one of the products mapped in our working capital finance guide, may fit better than invoice finance. The honest position for most limited-company subcontractors billing main contractors, though, is that a construction-specialist facility against certified applications is the closest match to how the business earns and spends.

The tax and CIS angle, and how to apply

Two tax points sit alongside the finance, and both are one hop away rather than something to solve on this page. First, the fees on an invoice or construction-finance facility are a normal business expense, deductible against corporation tax under the ordinary rules for finance costs (HMRC BIM45301). Second, the plant and vehicles a subcontractor buys are capital, not working capital: fund those through asset finance and you can claim capital allowances such as the annual investment allowance and, on qualifying new plant, full expensing, a separate decision from the receivables gap. Your CIS deductions, gross payment status and the corporation-tax position on all of this are questions for your accountant, and our trade specialists cover the CIS mechanics in full at Trade Tax Specialists.

Applying is quick because the funder underwrites your contracts and applications, not decades of history. Have ready your latest accounts or management figures, an aged debtor report, your main-contract documents and payment terms, a schedule of retentions held, your CIS registration and payment status, and a note of any live contra-charges or disputes. The clearer and cleaner that picture, the higher the advance rate and the faster the offer.

We introduce your limited company to a panel of commercial-finance brokers who work with construction-specialist funders, so you can compare advance rates against certified value, retention treatment and recourse terms side by side rather than taking the first line that will touch the sector. Complete the enquiry form below with your turnover band, your typical retention percentage, your main contractors and your CIS status. Separately, if you want to understand how the finance, your CIS position and capital allowances on plant interact, our accountants can advise on structure. The finance introduction and the tax advice are two different conversations, and we can help with both.

Authority sources for this guide: UK Finance (invoice finance and asset-based lending standards and statistics), the British Business Bank (business finance guidance), gov.uk business finance and support, gov.uk on the Construction Industry Scheme for the CIS framing, and the Financial Services and Markets Act 2000 (Regulated Activities) Order 2001 for the Article 36A company-borrower carve-out. Tax deductibility of finance costs follows HMRC BIM45301.