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

# Onboarding a Business

> Onboard one of your business customers to Layer

## Prerequisites

Before onboarding a business, you will need:

* An active Layer account and API credentials
* A valid access token (see [Initial Setup](/guides/initial-setup))
* Your customer's basic business information (legal name, entity type, state)

## Overview

The first step is to onboard your customer to Layer using the [Create a Business](/api-reference/business/create) endpoint. This creates a record for your customer in Layer's systems and provisions their general ledger.

<Steps>
  <Step title="Prepare business information">
    Gather the information about your customer's business. We recommend providing as much information as possible to help Layer accurately classify transactions and provide a better experience for your customer:

    * `legal_name` - The business's legal name
    * `entity_type` - One of: `SOLE_PROP`, `C_CORP`, `LLC`, `S_CORP`, `PARTNERSHIP`
    * `us_state` - Two letter state code
    * `external_id` - Your internal ID for this business, useful for linking records
    * `phone_number` - Used for SMS-based transaction categorization
    * `unit_accounts` - Array of Unit account IDs to link
    * `plaid_items` - Array of Plaid items to connect (requires Plaid configuration)

    <Info>
      The `external_id` field allows you to link the Layer business record to your own internal customer ID, making it easier to associate data between systems.
    </Info>
  </Step>

  <Step title="Create the business">
    Make a POST request to the [Create a Business](/api-reference/business/create) endpoint with the business information. See the full endpoint documentation for request examples and all available parameters.

    <Info>
      If you've configured Plaid credentials (see [Plaid Configuration](/api-reference/plaid/plaid)), you can link Plaid accounts during business creation by including the `plaid_items` field.
    </Info>
  </Step>

  <Step title="Save the business ID">
    The API responds with the created [Business](/api-reference/business/business) object. Save the `id` field - you'll use this to make API calls on behalf of this business.
  </Step>
</Steps>

## Next Steps

After onboarding a business, you can:

* [Import financial data](/guides/importing-data-overview) - Start passing transaction data to Layer
* [Set up transaction categorization](/guides/transaction-categorization) - Enable your customers to categorize transactions
* [Display accounting reports](/guides/reporting) - Show profit & loss, balance sheet, and other reports
* [Embed accounting components](/guides/embedded-components) - Add Layer's pre-built UI components to your platform