Issue one-off invoices

Create a one-off invoice

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

Select the customer from the list of customers
Click the Actions button in the upper-right corner, then select Create one-off invoice

Add add-ons to the invoice

Once you have started the flow, add one or several add-ons to the invoice:

Dashboard
API

Define a purchase order number, if needed
Select the Affiliated entity and the Invoice currency
Click Add an add-on to add a line item to the invoice
Set the number of units for the add-on
Define the add-on billing period (past, present, or future)
Edit the unit price, if needed (you can set it to 0)
Edit the description displayed on the invoice
Click Create one-off invoice to issue it

Create a one-off invoice dialog with two add-on line items, their units, unit prices and taxes — Adding add-ons to create a one-off invoice

See the create a one-off invoice endpoint for the full list of fields.

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",
      "billing_entity_code": "default",
      "purchase_order_number": "po-1234",
      "skip_psp": false,
      "fees": [
        {
          "add_on_code": "setup_fee",
          "invoice_display_name": "Implementation",
          "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",
          "invoice_display_name": "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"
        }
      ],
      "invoice_custom_section": {
        "skip_invoice_custom_sections": false,
        "invoice_custom_section_codes": ["eu_bank_details"]
      },
      "payment_method": {
        "payment_method_type": "provider",
        "payment_method_id": "1a901a90-1a90-1a90-1a90-1a901a901a90"
      }
    }
  }'

In this payload:

invoice_display_name replaces the add-on name on the invoice line.
skip_psp set to true creates the invoice without sending it to the payment provider.
invoice_custom_section picks the invoice custom sections printed on the PDF. The codes you list override the sections set on the customer and on the billing entity. Set skip_invoice_custom_sections to true to print none of them.
payment_method points to a payment method of this customer. Lago charges it only when skip_psp is false. payment_method_type is provider or manual.

Payment terms

You can choose a payment term for this invoice without changing the customer’s default. In Invoicing settings, select a term and enter its days or month settings before issuing the invoice. If you keep inheritance, the customer’s term applies. When the customer has none, the term of the billing entity selected for this invoice applies. For example, your customer’s subscription invoices use Net 30, but you agree Net 15 for a one-off setup fee. Set Net 15 on the setup-fee invoice. If both invoices are dated April 10, 2026, the setup fee is due April 25, while the subscription invoice is due May 10. See Payment terms for all six options and examples. The one-off invoice is issued immediately; the chosen term determines its payment deadline. Later changes to customer defaults do not change the term stored on this invoice. From the API, send payment_term when you create the one-off invoice. This endpoint does not accept the legacy net_payment_term field: if you send it, Lago ignores it and the inherited term applies.

Application scope of one-off invoices

A one-off invoice can include the same add-on several times.
The currency and billing entity of the one-off invoice can differ from the customer’s defaults: the invoice is issued in the currency and by the billing entity you select for it. Set billing_entity_code to pick the billing entity from the API.
You can reuse the same add-on for several customers, even when their subscriptions use different currencies. You can also charge a different amount to each of them.
Coupons or prepaid credits (discounts) do not apply to one-off invoices.
One-off invoices are subject to taxes. For each fee, Lago applies the tax_codes sent in the payload. If there are none, it falls back to the taxes of the add-on, then to the taxes of the customer, then to the default taxes of the billing entity. When the customer is connected to a tax provider such as Anrok or Avalara, the provider computes the taxes and the tax_codes of the payload are ignored.

When using the API endpoint, if unit_amount_cents is null, Lago applies the default amount of the add-on. If units is null, Lago bills 1 unit. If currency is null, Lago uses the currency of the customer. When the customer has no currency yet, the currency of this invoice becomes the customer’s currency.

Invoicing

A one-off invoice is issued straight away. Lago then sends the invoice.one_off_created webhook message.

Introduction

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Invoicing

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Revenue recognition

Resources

Issue one-off invoices

Create a one-off invoice

Add add-ons to the invoice

Payment terms

Application scope of one-off invoices

Invoicing