---
title: "What is a composite portfolio?"
slug: "what-is-a-composite-portfolio"
updated: 2025-12-12T12:36:17Z
published: 2025-12-12T12:36:17Z
canonical: "support.lusid.com/what-is-a-composite-portfolio"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://support.lusid.com/llms.txt
> Use this file to discover all available pages before exploring further.

# What is a composite portfolio?

A composite portfolio is a [transaction portfolio](/v1/docs/how-do-i-create-a-transaction-portfolio) that has a special kind of [relationship](/v1/docs/creating-relationships-between-certain-types-of-entity) with one or more other (constituent) transaction portfolios.

LUSID can perform complex operations on a composite portfolio, such as [aggregating performance return](/v1/docs/aggregating-performance-returns-for-a-portfolio) from all its constituent portfolios in order to calculate overall performance. For a worked example of creating a composite portfolio, see [this Jupyter Notebook](https://github.com/finbourne/sample-notebooks/blob/master/examples/use-cases/risk-and-performance/Returns%20on%20composite%20portfolios.ipynb).

To create a composite portfolio, you require a special license. This license enables you to create a relationship between the composite and each constituent portfolio using the built-in `CompositeMembership` relationship definition.

For more information, and to see how to acquire this license, [contact technical support](/v1/docs/how-do-i-use-the-support-centre).