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

# Issue one-off invoices

> One-off invoices allow you to bill immediately one or several add-ons to a customer.  This guide will show you how to create a one-off invoice for a specific customer using the add-ons.

## Create a one-off invoice

To create a one-off invoice for a specific customer:

1. Select the customer from the list of customers; and
2. Click the **"Actions"** button located in the upper-right corner and select **"Create one-off invoice"**.

## Adding add-ons to one-off invoices

Now that you have started the flow to create a one-off invoice, it's time to add one or several add-ons to it:

<Tabs>
  <Tab title="Dashboard">
    1. Click **"Add an add-on"** to add a new add-on to the invoice;
    2. Edit the number of units applied for a specific add-on;
    3. Define the billing period of the add-on, this period can be set in the past, now or in the future;
    4. Edit the unit price of a specific add-on (you can define it as 0 if needed);
    5. Edit the description of the add-on displayed on the invoice; and
    6. Click **"Create"** to issue your one-off invoice.

    <Frame caption="Adding add-ons to create a one-off invoice">
      <img src="https://mintcdn.com/lago/UEPn_6YXhKfpBUTK/guide/one-off-invoices/images/one-off-invoices.png?fit=max&auto=format&n=UEPn_6YXhKfpBUTK&q=85&s=7dbeacd229df8bef84423b405b121c50" width="3456" height="2161" data-path="guide/one-off-invoices/images/one-off-invoices.png" />
    </Frame>
  </Tab>

  <Tab title="API">
    ```bash Assign add-ons to create a one-off invoice theme={"dark"}
    LAGO_URL="https://api.getlago.com"
    API_KEY="__YOUR_API_KEY__"
    curl --location --request POST "$LAGO_URL/api/v1/invoices" \
      --header "Authorization: Bearer $API_KEY" \
      --header 'Content-Type: application/json' \
      --data-raw '{
        "invoice": {
          "external_customer_id": "hooli_1234",
          "currency": "USD",
          "fees": [
            {
              "add_on_code": "setup_fee",
              "units": 1,
              "unit_amount_cents": 50000,
              "description": "Implementation fee with a solution engineer",
              "from_datetime": "2025-01-01T00:00:00Z",
              "to_datetime": "2025-12-31T23:59:59Z"
            },
            {
              "add_on_code": "customer_success",
              "units": 2,
              "unit_amount_cents": 100000,
              "description": "One off customer success fee",
              "from_datetime": "2025-01-01T00:00:00Z",
              "to_datetime": "2025-12-31T23:59:59Z"
            }
          ]
        }
      }'
    ```
  </Tab>
</Tabs>

## Application scope of one-off invoices

Here are a few things to keep in mind about one-off invoices:

* One-off invoices are issued immediately and can include the same add-on multiple times.
* If the currency of the customer is already defined, the currency of the one-off invoice must be the same.
* You can use the same add-on to create one-off invoices for multiple customers whose subscriptions don't have the same currency or to apply a different amount for one of these customers.
* Coupons or prepaid credits (discounts) **do not apply** to one-off invoices.
* One-off invoices are subject to taxes, as defined in the customer view.

<Tip>
  Note that when using the API endpoint, if the amount and currency are null, Lago will apply the default amount and currency defined in the UI.
</Tip>

## Invoicing

As mentioned previously, a **one-off invoice is invoiced straight away**. You are able to find one-off invoices via a webhook message called `invoice.one_off_created`.