Remortgaging on CIS, umbrella or inside-IR35 income
CIS, umbrella and inside-IR35 contractors can all remortgage well, but each is easy to underassess if the lender reads the wrong figure. CIS subcontractors should be assessed on gross income before the 20% deduction; umbrella and inside-IR35 workers on the gross contract value, not the reduced net pay after deductions. The right lender uses the correct gross basis in each case, which usually supports far more borrowing than the net figure suggests.
Why are CIS, umbrella and IR35 contractors easy to underassess?
Answer first: because each one involves a gap between gross and net, and a lender reading the wrong side of that gap will understate your income. CIS deducts 20% at source; umbrella pay arrives after the umbrella’s deductions and costs; inside-IR35 work is taxed more like employment. In every case the net figure that lands in your account is smaller than the contract you actually earn — and a lender assessing the net figure caps your borrowing too low.
The remedy is the same across all three: be assessed on the correct gross basis by a lender that understands your arrangement. The borrowing is there; it’s a question of the lender reading the right number. The general process is in how to remortgage; this guide covers the income nuance for each arrangement.
Remortgaging on CIS income
A CIS subcontractor has 20% deducted at source under the Construction Industry Scheme, so the money received is already net of that deduction. The mistake is for a lender to assess you on that reduced figure. A CIS-friendly lender reads your gross posted income — the amount before the 20% deduction — using your CIS payslips, which reflects what you actually earn.
That difference is large: assessed gross rather than net, your borrowing capacity rises substantially. This mirrors how purchases work on our CIS subcontractors page, and it applies identically at remortgage. If your current lender has been working from your net figure, switching to one that reads the gross is often the single biggest improvement available to you.
Remortgaging on umbrella income
If you work through an umbrella company, your payslip shows pay after the umbrella’s margin, employer costs and deductions — a figure noticeably below your underlying contract rate. A lender that assesses umbrella take-home will undervalue you.
The right approach reads the gross contract value — the day rate you’re actually engaged at — rather than the umbrella net. A lender experienced with umbrella contractors knows to look through to the contract, which restores your true earning power to the assessment. Our umbrella and inside-IR35 page explains the assessment in more depth.
Remortgaging on inside-IR35 income
Being inside IR35 means your engagement is taxed more like employment, with tax and National Insurance deducted before you’re paid. It feels like it should limit your borrowing — but it doesn’t change whether you can borrow, only how you’re taxed. Lenders that understand contracting assess you on the gross contract value, so an inside-IR35 contractor can remortgage on essentially the same footing as others.
The pitfall is a lender that sees the reduced take-home and treats it as your income. The fix is a lender that reads the gross contract. Inside IR35 changes your tax position, not your worth to a sensible lender — a point worth holding onto if a high-street process has quoted you a disappointing figure.
How do you avoid being underassessed?
The single protection is lender choice. Across CIS, umbrella and IR35, the difference between a poor offer and a strong one is almost always whether the lender reads gross or net. A whole-of-market broker knows which lenders apply the correct gross basis for each arrangement and places your case accordingly — so you’re assessed on what you earn, not on what’s left after deductions.
It also helps to have the right evidence ready: CIS payslips for CIS, contract and umbrella payslips for umbrella work, and the contract for inside-IR35 engagements. The document checklist sets this out, and contract-based underwriting explains the mechanism that values the gross figure.
The bottom line
CIS, umbrella and inside-IR35 contractors can all remortgage well, but each is easy to underassess if the lender reads the net figure instead of the gross. CIS should be assessed before the 20% deduction; umbrella and inside-IR35 on the gross contract value. The right lender uses the correct basis in each case, which usually unlocks far more borrowing than your net pay suggests. To be assessed on what you genuinely earn, speak to an adviser.
- CIS subcontractors should be assessed on gross posted income, before the 20% CIS deduction.
- Umbrella workers are best assessed on the gross contract value, not net umbrella pay.
- Inside IR35 changes how you're taxed, not whether you can borrow — the gross contract still counts.
- Using the net figure in any of these cases understates income and shrinks borrowing.
- The right lender knows which gross basis applies, so lender choice protects your borrowing power.
Remortgage, answered
Can I remortgage as a CIS subcontractor?+
Yes. The key is being assessed on your gross income before the 20% CIS deduction, using your CIS payslips, rather than on the reduced figure after deductions. A CIS-friendly lender reads the gross posted income, which supports far more borrowing than the net amount that lands in your account.
Can I remortgage if I'm paid through an umbrella company?+
Yes. Umbrella workers can remortgage well when assessed on the gross contract value rather than the net pay after the umbrella's deductions and costs. The right lender looks at the underlying contract rate, which reflects your true earning power, not the smaller figure on your umbrella payslip.
Does being inside IR35 stop me remortgaging?+
No. Inside IR35 changes how your income is taxed, not whether you can borrow. Lenders that understand contracting assess you on the gross contract value, so an inside-IR35 contractor can remortgage on the same basis as others — provided the lender reads the gross figure rather than net take-home.
Why do some lenders offer me so little on this income?+
Usually because they read the net figure — after CIS deductions, umbrella costs, or IR35 tax — instead of the gross contract value. That understates your income and caps your borrowing. A lender set up for contractors uses the correct gross basis, which is why the same person gets very different answers from different lenders.