> For the complete documentation index, see [llms.txt](https://www.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://www.bluegamma.io/documentation/market-data-guides/bonds/iboxx-spreads.md).
# iBoxx Spreads
Index-level yield, OAS and Z-spread across infrastructure, corporate, sovereign, covered and inflation-linked bond indices, current and historical.
iBoxx Spreads gives you credit spreads at the index level rather than the individual bond. Use it to see where a sector, rating band or maturity bucket is trading, and how that has moved over time.
For a specific security rather than an index, use [Bond Comps](https://www.bluegamma.io/documentation/market-data-guides/overview-2/bond-comps).
***
### 1. Open iBoxx Spreads
From the left-hand navigation, click **Bonds** and then [**iBoxx Spreads**](https://app.bluegamma.io/bonds/iboxx).
The page splits into two panels: **Current Spreads** on the left, **Historical Spreads** on the right.
***
### 2. Current Spreads
A live table of every index we carry, with three measures against each:
| Column | What it means |
| -------------- | ---------------------------------------------------------------------------------------------------------- |
| **Index Name** | The index, for example `iBoxx EUR Infrastructure 10+Y Index` |
| **Yield (%)** | The index yield |
| **OAS** | Option-adjusted spread in basis points, stripping out the value of embedded options such as calls |
| **Z-Spread** | Zero-volatility spread in basis points, the constant spread over the risk-free curve that prices the index |
OAS and Z-spread differ where the constituents carry embedded options. For an index with none, the two sit close together.
Use **Search Spreads** to filter by name, or **Filters** to narrow the list. The **Last update** timestamp sits below the table.
{% hint style="info" %}
A dash in a column means the measure is not published for that index. Sovereign and inflation-linked families often carry a yield without a Z-spread.
{% endhint %}
***
### 3. Historical Spreads
Select a **Spread Type** and an **Index** to chart how that measure has moved. Click **Download** to export the series.
***
### 4. What Is Covered
The index universe spans several families:
* **Infrastructure and regulated utilities** in EUR, GBP and USD, broken down by maturity band (1-3Y through 15+Y), rating (AAA to BBB, plus high yield) and sector (telecommunications, transportation, utilities)
* **Corporates** by currency, rating, maturity band and country of risk
* **Sovereigns and sub-sovereigns**, including eurozone country indices and liquid sovereign series
* **Covered bonds** by jurisdiction and maturity
* **Inflation-linked** indices for the UK, US TIPS, France, Germany, Italy, Spain, Sweden, Japan, Korea and Australia
* **Asian and Australian** families, including ABF, ALBI and the S\&P/ASX iBoxx series
* **Green, social and sustainability** indices, hedged and unhedged
Infrastructure indices aggregate a basket of infrastructure bonds in the same currency, covering electricity, gas distribution, pipelines and water. Issuers with material infrastructure exposure are also included depending on the profile of the issuer.
***
### Related
[Bond Comps](https://www.bluegamma.io/documentation/market-data-guides/overview-2/bond-comps)
[Government Bonds](https://www.bluegamma.io/documentation/market-data-guides/overview-2/government-bonds)
[FAQs](https://www.bluegamma.io/documentation/market-data-guides/overview-2/faqs)
---
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