Borrowing Base Defined
A borrowing base is the maximum amount a borrower can draw under an asset-backed revolving credit facility at any given point in time. Unlike a traditional unsecured credit line where the full commitment is available regardless of assets, a borrowing base facility ties the available amount directly to the value of eligible collateral , typically accounts receivable, inventory, or a combination of both.
In the context of AR securitization, the borrowing base is calculated by starting with gross receivables, subtracting ineligible amounts, applying an advance rate to the eligible pool, and then deducting reserves. The result is a dynamic number that fluctuates daily as new receivables are generated, existing invoices are paid, and portfolio quality metrics change.
The borrowing base is documented in a Borrowing Base Certificate (BBC), a formal report submitted by the borrower to the lender at regular intervals. The BBC is a critical document in asset-backed lending because it determines exactly how much liquidity the borrower can access at any given time.
BBC Calculation: Step by Step
The borrowing base calculation follows a waterfall structure, with each step reducing the gross receivables balance down to the final available amount. Here is a typical calculation with illustrative numbers:
| Step | Description | Example |
|---|---|---|
| Gross Accounts Receivable | The starting point is the total face value of all trade receivables on the originator's ledger. This includes all open invoices regardless of age, obligor quality, or dispute status. | $25,000,000 |
| Less: Ineligible Deductions | Receivables that fail one or more eligibility criteria are removed. Common reasons include aging past the limit, cross-aging disqualification, concentration excess, affiliate receivables, disputed invoices, and receivables on credit hold. | ($5,250,000) |
| Eligible Receivables | The remaining receivables after all ineligible deductions. This is the pool of collateral that will be advanced against. | $19,750,000 |
| Apply Advance Rate | The advance rate (e.g., 85%) is applied to eligible receivables to determine the gross borrowing base. Some facilities use tiered rates by aging bucket. | x 85% = $16,787,500 |
| Less: Reserves | Reserves are subtracted to cover potential losses. These include dilution reserve, yield reserve, loss reserve, and servicing reserve. Each is calculated using formulas defined in the facility agreement. | ($1,350,000) |
| Net Borrowing Base | The net borrowing base is the maximum amount available for borrowing based on the collateral alone, before considering the facility limit. | $15,437,500 |
| Available Amount | The actual amount the borrower can draw is the lesser of the net borrowing base and the facility limit, minus any outstanding draws. | min($15,437,500, $20,000,000) - $10,000,000 = $5,437,500 |
Advance Rates and Reserve Types
Advance Rates by Aging Bucket
Most facilities assign different advance rates to receivables based on their age. Current receivables command the highest advance rates, while older receivables receive progressively lower rates or are excluded entirely.
| Aging Bucket | DPD Range | Typical Advance Rate |
|---|---|---|
| Current | 0-30 days | 85-90% |
| 30+ Days | 31-60 days | 70-80% |
| 60+ Days | 61-90 days | 50-60% |
| 90+ Days | 91+ days | 0% (excluded) |
Reserve Types
Reserves are deducted from the gross borrowing base to provide a cushion against various risks. Each reserve type has a specific formula and purpose defined in the facility agreement.
Yield Reserve
Advance Rate x Weighted Avg. Rate x Weighted Avg. Days / 360
Protects the lender against the cost of carrying the funded amount during the collection period. It ensures that even if the originator defaults as servicer, sufficient funds are reserved to cover interest costs.
Dilution Reserve
3-Month Rolling Avg. Dilution Rate x Stress Factor
Covers expected reductions in receivable value from credits, rebates, returns, and disputes. The stress factor (typically 1.5-2.0x) provides a buffer above historical dilution levels.
Loss Reserve
Stress Factor x Default Rate x Loss Horizon (months) / 12
Protects against potential defaults by obligors. The loss horizon represents the estimated time to liquidate the collateral, and the stress factor provides a cushion above historical loss rates.
Servicing Reserve
Estimated Annual Servicing Cost / 12 x Collection Period
Covers the cost of engaging a replacement servicer if the originator can no longer collect the receivables. Typically ranges from 0.5-1.0% of the outstanding balance.
The Borrowing Base Certificate (BBC)
The Borrowing Base Certificate is the formal document that the borrower submits to the lender certifying the current borrowing base amount. It is both a compliance requirement and a practical tool for managing facility utilization.
A typical BBC contains: the calculation date, gross receivables balance, a detailed breakdown of ineligible deductions by category, the resulting eligible receivables balance, advance rate applied, reserve amounts by type, the net borrowing base, the facility limit, outstanding draws, and the final available amount. Many BBCs also include supporting schedules such as obligor concentration reports, aging summaries, and covenant compliance calculations.
Who submits it: The borrower (originator or servicer) is responsible for preparing and certifying the BBC. An authorized officer must sign the certificate, attesting to its accuracy.
Frequency: Monthly submission is standard, with many programs requiring weekly or daily recalculations for larger facilities. The certificate is typically due within 10-15 business days after each reporting period.
Triggers for recalculation: Material adverse changes in the portfolio, such as a large obligor default, a sudden spike in dilution, or a covenant breach, can trigger mandatory interim BBC submissions outside the regular schedule.
Common Eligibility Criteria
Not all receivables on the borrower's ledger qualify for inclusion in the borrowing base. The facility agreement defines a set of eligibility criteria that each receivable must pass before it can be counted as collateral.
Aging Limits
Receivables must be within a specified number of days past due (DPD), typically 60 or 90 days from the original invoice due date. Receivables exceeding the aging limit are automatically excluded from the eligible pool.
Cross-Aging Rule
When a specified percentage (commonly 50%) of an obligor's total receivables exceed the aging threshold, all receivables from that obligor become ineligible, even invoices that are not yet past due. This reflects the increased credit risk associated with delinquent payers.
Concentration Limits
No single obligor (or group of affiliated obligors) may represent more than a specified percentage of the total eligible pool, typically 5-10% depending on the obligor's credit quality. The excess above the concentration limit is excluded.
Minimum Invoice Amount
Invoices below a minimum dollar threshold (e.g., $100 or $500) may be excluded to reduce administrative burden and eliminate micro-receivables that are disproportionately expensive to track and collect.
Ineligible Categories
Entire categories of receivables may be excluded by contract: intercompany receivables, government receivables (which may have special offset rights), receivables from obligors in bankruptcy, disputed invoices, consignment sales, and receivables with non-standard payment terms.
Currency and Jurisdiction
Receivables denominated in foreign currencies or payable by obligors in excluded jurisdictions may be ineligible. Foreign-currency receivables introduce exchange rate risk, while cross-border collections involve additional legal complexity.
Payment Terms
Invoices with extended payment terms beyond a contractual maximum (e.g., net 90 or net 120) may be excluded. Longer payment terms increase the duration risk and the likelihood that the receivable will age past the DPD limit.
How Olycor Automates Borrowing Base Calculations
Preparing a borrowing base certificate manually in spreadsheets is time-consuming, error-prone, and impossible to audit at scale. Olycor automates the entire workflow:
Borrowing Base Calculator
Automated BBC computation with advance rate tiers, concentration adjustments, and dynamic reserve formulas. Generates investor-ready certificates in under 3 seconds.
Eligibility Engine
Invoice-level eligibility testing with full explainability. See the exact rule, threshold, actual value, and source data for every pass/fail determination.