An interbank rate is the interest rate on a specified bank-to-bank funding transaction or benchmark, defined by currency, tenor, collateral, market, and methodology.
An interbank rate is the annualized interest rate paid, observed, or quoted for funds exchanged between banks in a specified market. The term is incomplete without the currency, tenor, secured or unsecured status, transaction type, observation time, and rate source.
There is no single global interbank rate. An overnight reserve trade, a three-month unsecured deposit quote, and a secured repo transaction can all produce different rates even on the same day.
A usable rate description should specify:
Without these fields, comparing two “interbank rates” can be misleading.
| Category | Typical interpretation | Example |
|---|---|---|
| Overnight unsecured | One-business-day borrowing without collateral | Effective federal funds rate; TONA |
| Overnight secured | One-business-day cash borrowing against securities | SOFR market transactions |
| Unsecured term benchmark | Term bank or wholesale funding conditions | EURIBOR, HIBOR |
| Offered quotation | Rate at which a bank indicates willingness to lend | Some historical and current IBOR methodologies |
| Bid quotation | Rate at which a bank indicates willingness to borrow | Historical LIBID usage |
Some modern benchmark populations include nonbank financial counterparties, so even a rate descended from interbank-market practice may not be based exclusively on bank-to-bank transactions.
| Term | Meaning |
|---|---|
| Transaction rate | Price agreed by counterparties on one trade |
| Interbank benchmark | Standardized value calculated under an administrator methodology |
| Quote | Indication or submission that may not represent a completed trade |
| Policy rate | Central-bank target or administered facility rate |
| Customer rate | Rate charged on a loan or paid on a deposit after product-specific pricing |
Central-bank policy strongly influences short-term funding, but an observed interbank rate can differ from the policy target because of liquidity, reserve distribution, collateral, credit, and market structure.
An unsecured term interbank rate can be interpreted conceptually as:
For secured funding, collateral effects also matter:
These are analytical decompositions, not formulas that can be reproduced from one public data point. The components interact and are estimated differently across models.
Suppose a bank can borrow $50 million overnight at:
4.85% against eligible collateral5.10% without collateralThe observed unsecured-secured difference is:
On an Actual/360 basis, one day of unsecured interest is:
The 25-basis-point difference cannot be attributed entirely to credit risk. Collateral value, repo specialness, transaction venue, counterparty, and liquidity can also contribute.
A floating-rate customer loan may be expressed as:
The borrower margin can reflect:
A lower interbank benchmark does not guarantee cheaper credit for every borrower, and a benchmark can fall while credit spreads rise.
Overnight interbank and wholesale rates are early links in monetary-policy transmission. Central-bank operations and administered rates influence them, and their movement can pass through to broader yields and financing conditions.
The rates show the marginal price of obtaining or placing short-term funds within a defined segment. They help treasury teams compare unsecured borrowing, repo, deposits, central-bank facilities, and other sources.
Published benchmarks derived from funding markets can set floating coupons, derivative cash flows, discount curves, and hedge measurements.
Wider unsecured-versus-overnight-indexed or secured spreads can indicate greater credit or liquidity concerns. Analysts must check transaction volume and market structure before drawing that conclusion.
Match:
For example, comparing three-month EURIBOR with overnight SOFR mixes currency, tenor, security, and methodology. The numerical spread does not isolate one economic factor.
This article provides general financial education, not personalized investment, borrowing, accounting, tax, or legal advice. Use exact benchmark methodologies and governing contracts for operational decisions.