Finance Calculator
Invoice Discounting Availability Calculator
Estimate the available funding under a confidential invoice discounting facility. Enter your debtor book value, exclusion percentages, and advance rate to see a detailed breakdown.
Enter your debtor book details
How is discounting availability calculated?
Invoice discounting availability starts with the total debtor book and removes invoices that the lender considers ineligible. The remaining eligible book is then multiplied by the advance rate to determine the maximum funding available at any time.
Ineligible debtors typically fall into three categories:
- Concentration: Where a single debtor exceeds the lender's maximum concentration limit (typically 25–30% of the book).
- Overdue / disputed: Invoices significantly past payment terms or under dispute.
- Other exclusions: Overseas debtors, contra balances, intercompany debts, pre-invoiced amounts, etc.
The formulas used in this calculator are:
Ineligible Amount = Book × (Concentration% + Overdue% + Other%)
Eligible Debtor Book = Total Book − Ineligible Amount
Available Funding = Eligible Book × Advance Rate
Retention = Eligible Book − Available Funding
Assumptions and caveats
- •Exclusion percentages are illustrative. Actual ineligible amounts depend on your specific debtor profile and the lender's criteria.
- •Availability is recalculated regularly (often daily) based on changes to the debtor book.
- •Some lenders apply disapproval reserves or additional dilution adjustments not modelled here.
- •Advance rates vary by provider, sector, and the quality of the debtor book.
- •Results are indicative only. Contact a specialist for a formal availability calculation.
Frequently asked questions
Invoice discounting is a form of asset-based finance where a business borrows against the value of its outstanding invoices. Unlike factoring, invoice discounting is typically confidential — your customers are unaware of the arrangement and you retain full control of credit management and collections.
Lenders apply eligibility criteria to the debtor book to manage risk. Common exclusions include concentration limits (where a single debtor represents too large a share of the book), overdue or disputed invoices, overseas debtors without credit insurance, related-party debts, and invoices subject to contra trading arrangements.
Debtor concentration measures how reliant your sales are on a single customer. If one debtor represents a disproportionate share of the book (commonly above 25–30%), the lender may exclude the excess amount. This reduces portfolio risk and protects the facility if that debtor fails to pay.
Availability is typically recalculated daily or weekly based on the latest debtor book position. As new invoices are raised and existing ones are paid or become overdue, the eligible book and available funding will fluctuate. Most providers use an online platform that shows real-time availability.
Looking for invoice discounting?
The Spark team can assess your debtor book and match you with the right confidential invoice discounting provider.
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