Published 2026-07-19 · Contractor Mortgage Guide · Written and reviewed by Phillip Wakeling-Smith (CeMAP)

How much can I borrow on my day rate? The contractor borrowing formula

Q: How many times my day rate income can I borrow?

Typically 4.5× the lender's annualised assessment of your day rate, with 5–5.5× available for stronger profiles at some lenders. The bigger variable is usually the annualisation itself — 41 vs 52 weeks changes your assessed income by over a quarter before any multiple is applied.

Quick answer: For a contractor assessed on a day-rate basis, borrowing is roughly day rate × 5 days × the lender's weeks-per-year multiplier × the lender's income multiple — and because both multipliers vary by lender, the honest answer is a range, not a number. At £500/day, assessed income runs from about £102,500 (41 weeks) to £130,000 (52 weeks) across our verified panel — which at typical income multiples is a borrowing spread of well over £100,000 on the identical contract. Your ceiling depends on which lender you ask: see your own spread in the day-rate calculator.

The formula, step by step

1. Annualised income = day rate × days per week × weeks. Lenders don't take 52 weeks × 5 days at face value — each applies its own weeks assumption (typically 41–48, a few at 52 for specific contract types) to allow for gaps and holidays. This single assumption creates most of the lender-to-lender spread — the full lender-by-lender breakdown is in how lenders turn a day rate into a mortgage.

2. Income multiple: typically 4.5×, up to 5–5.5× for stronger cases. Applied to the annualised figure. Higher multiples usually need higher income, lower loan-to-value, or both — and not every lender that's generous on annualisation is generous on multiple.

3. Deductions and commitments come off before the multiple does its work. Pension contributions visible on payslips, car finance, childcare and other committed outgoings all reduce the assessable position — this is where two contractors on the same rate with different outgoings diverge.

Rough ranges by day rate

Illustrative assessed-income ranges using the 41–52-week spread on a 5-day week (before multiples, deductions and your specific circumstances — use the calculator for your actual figure):

| Day rate | Assessed income range | ~Borrowing at 4.5× | |---|---|---| | £300 | £61,500 – £78,000 | £277k – £351k | | £400 | £82,000 – £104,000 | £369k – £468k | | £500 | £102,500 – £130,000 | £461k – £585k | | £650 | £133,250 – £169,000 | £600k – £760k |

The right-hand column is the theoretical multiple-driven ceiling — real offers also pass through affordability models where outgoings and rates bite. The affordability check runs a full multi-lender assessment rather than a multiple.

What moves you up (or down) the range

Contract type: umbrella, Ltd and CIS are read differently — some lenders only run their day-rate route for certain structures. Check yours in the contract-type checker.
History and gaps: 12+ months' contracting with tidy renewals unlocks more lenders; gaps over ~6 weeks trigger pro-rating or declines at some — see contract history and gaps.
Time left on the current contract: several lenders want 3+ months remaining or evidence of renewal (timeline checker).
First-time contractors are the most lender-sensitive case of all — covered in the first-time contractor guide.

FAQ

How many times my day rate income can I borrow?

Typically 4.5× the lender's annualised assessment of your day rate, with 5–5.5× available for stronger profiles at some lenders. The bigger variable is usually the annualisation itself — 41 vs 52 weeks changes your assessed income by over a quarter before any multiple is applied.

Do lenders use my day rate or my accounts?

Both routes exist. Contractor-friendly lenders annualise the contract rate (usually the higher figure for genuine day-rate contractors); others assess you as self-employed on accounts or umbrella payslips. Which route a given lender runs — and for which contract types — is exactly what the contract-type checker maps.

What deposit do I need as a contractor?

The same LTV bands as anyone else in principle — but some lenders cap contractor LTV more tightly, especially with short history. See the contractor LTV checker.

Is there a quick way to see what different lenders would lend me?

Yes — the day-rate calculator shows the assessed income at each lender on our panel from one day rate, and the embedded affordability check runs a wide-panel borrowing estimate from your full circumstances.