Borrow on your gross income — before the 20% comes off.
Most lenders treat you as self-employed and judge you on net profit after expenses, shrinking what you can borrow. CIS-friendly lenders use your gross posted income from your payslips — and the figure is usually far higher.
Stuck between employed and self-employed
Work under the Construction Industry Scheme and the tax never lands in your account at all: whoever engages you withholds it first — 20% where you are registered, 30% where you are not — and sends it to HMRC on your behalf. The result is a status most high-street systems simply cannot categorise: you are neither an employee nor a conventional sole trader.
The result is that standard lenders default to treating you as self-employed and ask for two or three years of accounts. Those accounts show net profit after expenses, which understates your earning power — and if you’ve been subcontracting under a year, you may not have them at all. Either way, the door tends to close.
How do CIS-friendly lenders see it differently?
A group of specialist lenders assess CIS subcontractors closer to employed applicants. Rather than digging through self-assessment, they:
- Average your last three to six months of gross CIS payslips to estimate annual income.
- Use that gross figure — before the 20% deduction — as the basis for affordability.
- Apply an income multiple, commonly in the 4× to 5× range depending on the lender and profile.
- Accept payslips in place of full business accounts, which helps if you’re newly self-employed.
Gross vs net: what difference does it make?
Same earnings, two assessments
Net profit shown on self-assessment: £38,000
Self-employed basis at 4.5×: ≈ £171,000
CIS gross basis at 4.5×: ≈ £270,000
Same work, same money. Assessed on gross posted income, the borrowing rises substantially.
What documents do you need?
- Three to six months of CIS payslips or contractor statements.
- Three to six months of personal bank statements.
- Proof of CIS registration where applicable.
- Proof of deposit, identity and address.
- Latest SA302 and Tax Year Overview if you have them — useful, not always essential.
Estimate your borrowing
Enter your gross annual income below — the figure before the 20% CIS deduction — to see the borrowing it could support.
CIS mortgages, answered
What is a CIS mortgage?+
It is not a separate product — it is a mortgage assessed on the way Construction Industry Scheme subcontractors are paid. The right lenders treat you closer to employed, using your gross CIS income before the 20% tax deduction, rather than the lower net-profit figure from your tax return.
Can I borrow more on gross income than on my SA302?+
Usually, yes. Self-assessment accounts deduct business expenses and show net profit, which shrinks affordability. CIS-friendly lenders average your recent gross payslips instead, which is typically a higher figure — so the same income can support a larger mortgage.
How many payslips do I need?+
Most CIS lenders average your last a recent run of CIS statements — commonly a few months' worth — and works an annual gross figure up from them. Where those payslips are consistent, that is frequently sufficient on its own, with no need for two years of finalised accounts.
What if I’ve been subcontracting for less than a year?+
You still have options. Some lenders accept a shorter CIS history where your payslips and contract continuity support it, which is why subcontractors new to self-employment should speak to a specialist rather than assume a high-street decline is final.
Do I need to be a registered CIS subcontractor?+
Registered subcontractors have 20% deducted at source; unregistered ones face 30%. Being registered generally gives access to more lenders and a cleaner assessment, but advice is available either way.