> For the complete documentation index, see [llms.txt](https://bluegamma.io/documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bluegamma.io/documentation/market-data-guides/overview-1.md). # Swap Rates A comprehensive introduction to interest rate swaps, how they work, and how they are priced {% hint style="info" %} Already know how swaps work? Skip straight to [Swap Rates in BlueGamma](#swap-rates-in-bluegamma) to see the page itself. {% endhint %} ## What Is an Interest Rate Swap? An **interest rate swap** is a financial derivative contract where two parties agree to exchange interest rate payments over a set period. The most common type is a **vanilla interest rate swap**, where one party pays a fixed rate and receives a floating rate, while the other party does the opposite.
**Key characteristics:** * No exchange of principal — only interest payments are swapped * Payments are typically **netted** (only the difference is paid) * The notional amount is used only for calculating interest *** ## Why Use Interest Rate Swaps? ### 1. Hedging Interest Rate Risk The most common use case. A borrower with a **floating-rate loan** can enter a swap to effectively convert it to a fixed rate, protecting against rising interest rates. **Example:** A company borrows €50M at EURIBOR + 2%. They're exposed to EURIBOR fluctuations. By entering a swap where they pay fixed and receive EURIBOR, they lock in their total borrowing cost. ### 2. Speculation Traders can take positions on the direction of interest rates without borrowing or lending actual funds. ### 3. Arbitrage Exploiting pricing differences between markets or instruments. *** ## The Two Legs of a Swap An interest rate swap consists of two sets of cashflows: ### The Fixed Leg * Pays a **fixed interest rate** (the "swap rate") on the notional amount * Rate is determined at the start of the contract and remains constant * Typically paid annually or semi-annually ### The Floating Leg * Pays a **variable interest rate** based on a reference index * Common indices: **SOFR** (USD), **SONIA** (GBP), **EURIBOR** (EUR), **ESTR** (EUR OIS) * Rate resets periodically (e.g., every 3 or 6 months) * Often includes a spread over the index **Payment Schedule Example (5-Year Swap):**
The fixed leg pays once per year at a rate locked in at inception. The floating leg pays quarterly, with the rate resetting each period based on the reference index. *** ## How Is the Swap Rate Determined? At inception, a swap is priced so that the **present value of both legs is equal** — meaning the swap has zero value to both parties (before any spreads are added). $$PV(\text{Fixed Leg}) = PV(\text{Floating Leg})$$ The fixed rate that satisfies this equation is called the **par swap rate** or **mid-rate**. ### What Drives Swap Rates? * **Forward rate expectations** — Market expectations of future floating rates * **Supply and demand** — Hedging activity and speculative positioning * **Credit conditions** — Interbank lending conditions affect swap spreads *** ## Breaking Down the Swap Rate When you receive a swap quote from a bank, the rate typically includes three components: $$\text{Swap Rate} = \text{Mid-Rate} + \text{Execution Spread} + \text{Credit Spread}$$ | Component | Description | | -------------------- | --------------------------------------------------------------------------------------------------------- | | **Mid-Rate** | The theoretical fair rate where PV(Fixed) = PV(Floating) | | **Execution Spread** | Compensates the bank for market/liquidity risk when executing | | **Credit Spread** | Compensates the bank for counterparty credit risk, its cost of funding collateral, and regulatory capital | The credit spread is the least visible of the three, and usually the largest surprise. It covers the credit risk the bank takes on you for the life of the trade, and banks can pass the cost of hedging that risk straight through into your quote. It also covers the cost of funding collateral on the position, and the regulatory capital the bank has to hold against the trade for as long as it stays open. Those costs scale with tenor and with your credit quality, which is why the same 5Y and 15Y mid-rate can come back with very different all-in quotes. {% hint style="info" %} **Pro Tip:** Always request a breakdown of the swap rate into its components for full transparency. BlueGamma shows the mid-rate, so you can compare it against bank quotes to understand the total spread being charged. {% endhint %} *** ## Example: Hedging a Floating-Rate Loan **Scenario:** A company has a €10M loan at 6M EURIBOR + 1.5% margin for 5 years. **Problem:** If EURIBOR rises from 2% to 5%, their interest cost increases significantly. **Solution:** Enter a 5-year interest rate swap: * **Pay fixed:** 2.58% (the current 5Y swap rate) * **Receive floating:** 6M EURIBOR **Result:** | Cash Flow | Rate | | ------------------------------ | -------------- | | Pay to lender | EURIBOR + 1.5% | | Pay on swap (fixed leg) | + 2.58% | | Receive on swap (floating leg) | − EURIBOR | | **Net borrowing cost** | **4.08%** | **How it works:** The EURIBOR you receive from the swap offsets the EURIBOR you pay to the lender — these cancel out. What remains is: * The **swap fixed rate** (2.58%) — your new "base" interest cost * The **loan margin** (1.5%) — still paid to the lender on top Total: 2.58% + 1.5% = **4.08% fixed**, regardless of where EURIBOR moves. *** ## Key Terminology | Term | Definition | | ------------------------ | ------------------------------------------------------------------------ | | **Notional** | The principal amount used to calculate interest payments (not exchanged) | | **Tenor** | The length of the swap (e.g., 5 years, 10 years) | | **Effective Date** | When the swap starts accruing interest | | **Maturity Date** | When the swap ends | | **Day Count Convention** | Method for calculating interest (e.g., Actual/360, 30/360) | | **Payment Frequency** | How often payments are made (e.g., quarterly, annually) | | **Mark-to-Market (MtM)** | The current value of the swap based on market rates | *** ## Swap Rates in BlueGamma Every currency and index we cover has its own page. Taking **SONIA** as the example, at `app.bluegamma.io/gbp/sonia`:
**At the top**, a live badge and timestamp show whether quotes are still updating. Beside them sits a countdown to the Bank of England's upcoming decision, with the odds the market is pricing for it. **The chart** plots a single tenor through time, over any window from **1D** to **Max**. The line underneath spells out the convention behind the number, `Overnight Index Swap ACT/365 Fixed Annual vs SONIA`, which is what makes the level comparable to a quote from anywhere else. **The table** lists the par swap rate at every quoted tenor, with the live level alongside where it stood 1D, 1W, 1M and 1Y ago, and a 3M sparkline. Reading across a row tells you whether today is a move or a continuation. **Show all 39 tenors** expands past the headline set, **Graph** switches the same data to a curve view, and **Download** exports it. **Click any tenor** to open that single point on its own, with price history, the forward starting rate, volatility cones, and a day-by-day historical table. {% hint style="warning" %} The rates on this page are **mid-market par rates for a bullet (non-amortising) profile**. If your loan amortises, the bullet rate is not the rate you will pay — price the actual schedule in the [Swap Pricer](https://www.bluegamma.io/documentation/pricers/calculating-a-swap-rate) instead. {% endhint %} *** ## Next Steps * [Calculating a Swap Rate](https://www.bluegamma.io/documentation/pricers/calculating-a-swap-rate) — Learn how to price a swap using BlueGamma * [Calculating the MtM of a Swap](https://www.bluegamma.io/documentation/pricers/calculating-the-mtm-of-a-swap) — Value an existing swap position * [Fetching a Swap Curve](https://www.bluegamma.io/documentation/integrations/api/how-to-guides/fetching-a-swap-curve) — Get swap rates via API --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://bluegamma.io/documentation/market-data-guides/overview-1.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.