---
title: "How do I create a side?"
slug: "how-do-i-create-a-side"
updated: 2025-02-04T09:15:44Z
published: 2025-02-04T09:15:44Z
canonical: "support.lusid.com/how-do-i-create-a-side"
---

> ## 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.

# How do I create a side?

You can create a [side](/v1/docs/what-is-a-side) to determine how a [movement](/v1/docs/what-is-a-movement) in a [transaction type](/v1/docs/what-is-a-transaction-type) to which the side is ultimately assigned impacts a holding.

Note the following:

- LUSID provides a set of [built-in sides](/v1/docs/what-built-in-transaction-types-and-sides-are-provided-with-lusid#builtin-sides). It might be worth checking whether one of these is suitable before creating a custom side.
- You can assign a side to any number of movements in any number of transaction types, providing those transaction types are domiciled in the same scope as the side.
- Once assigned to movements in live transaction types, you should only modify a side under exceptional circumstances.
- If you do modify a side, the PUT `SetSide*` APIs operate differently to the standard PUSH `Upsert*` model used elsewhere in LUSID. A side is *replaced* rather than updated, so it's important to specify the entire definition each time. And note the `SetSideDefinitions` API replaces *all* sides in a scope.

For examples of creating custom sides, see the following tutorials:

- [Reducing the cash balance by the cost of broker commission](/v1/docs/reducing-the-cash-balance-by-the-cost-of-broker-commission)
- [Breaking out broker commission as a separate cost holding](/v1/docs/breaking-out-broker-commission-as-a-separate-cash-holding)

## Using the LUSID REST API

1. Call the [SetSideDefinition](https://www.lusid.com/docs/api/#operation/SetSideDefinition) API to create a side in a particular scope (see below), or the [SetSideDefinitions](https://www.lusid.com/docs/api/#operation/SetSideDefinitions) API to create all your sides in a scope in a single operation, passing in your API token and specifying the following parameters in the URL:

[More information about transaction type scopes](/v1/docs/grouping-related-transaction-types-using-scopes-and-sources).
  - A `side` name uniquely identifying the side in its scope.
  - A `scope` if transaction types to which the side will ultimately be assigned are domiciled in a custom transaction type scope. If you omit this parameter, the side is created in the `default` scope, and can only be assigned to transaction types domiciled in the `default` scope.
2. In the body of the API request, specify:
  - One of the [allowed values](/v1/docs/what-is-a-side) for each of the mandatory `security`, `currency`, `rate`, `units` and `amount` fields.
  - Optionally for transactions in Future or CFD instruments, one of the [allowed values](/v1/docs/what-is-a-side#notional-amount) for the `notionalAmount` field, for example the `Transaction/default/NotionalAmount` [system property](/v1/docs/what-is-a-system-property#transaction-system-properties).

Consider the following example of a call to the `SetSideDefinition` API:

```json
curl -X PUT 'https://<your-domain>.lusid.com/api/api/transactionconfiguration/sides/BuyWithCommission?scope=Ibor'
  -H 'Content-Type: application/json-patch+json'
  -H 'Authorization: Bearer <your-API-access-token>'
  -d '{
  "security": "Txn:SettleCcy",
  "currency": "Txn:SettlementCurrency",
  "rate": "SettledToPortfolioRate",
  "units": "Transaction/MyProperties/Commission",
  "amount": "Transaction/MyProperties/Commission",
  "notionalAmount": "Transaction/default/NotionalAmount"
}'
```

## Using the LUSID web app

1. [Sign in to the LUSID web app](https://www.lusid.com/app/home).
2. Navigate to the **System Settings > Transaction Types** dashboard and open the **Sides** tab (highlighted in red).
3. Click the **Add side** button (highlighted in green) and follow the instructions: ![](https://cdn.document360.io/d575ad81-c0ed-4980-bbd1-d59ac5c3de82/Images/Documentation/028a428f-03ff-4d47-90fd-0b3bc2f0d4b5.png)