---
title: "Part sale – sell a part from a serial-number product"
description: "Sell a single part from a machine (serial-number product) directly from a sales order or invoice line. The customer pays for the part, and the part's cost price is deducted from the machine's value."
url: https://support.sapera.io/en/articles/772-part-sale-sell-a-part-from-a-serial-number-product
collection: "Sales orders"
updated: 2026-11-08
language: en
alternates: [da]
---

# Part sale – sell a part from a serial-number product

Sell a single part from a machine (serial-number product) directly from a sales order or invoice line. The customer pays for the part, and the part's cost price is deducted from the machine's value.

With a part sale you can sell a single part – for example a wheel or an engine – from a machine that is in stock as a serial-number product. The customer pays for the part like an ordinary sale, and the part's cost price is deducted from the machine's stock value and placed on the sales line.

A part sale is not the same as partial invoicing (invoicing part of a sales order at a time) – for that, see [How to partially invoice a sales order](https://support.sapera.io/en/articles/583.md).

## Before you start

Create an action code with **Account settings = Part sale (line serial-number product)** under **Setup** and **Action codes**, and give it a meaningful name. The part must be a stocked product, and the invoice must use stock.

If you cannot see the menu item, you probably do not have permission for it – contact support.

## How to sell a part

1.  Open **Financial** from the hamburger menu in the top left corner. Select **Sales** and then **Sales orders** (a part sale can also be used on an invoice that comes from a sales order).
    

1.  Add a line with the part you are selling.
    

1.  Select the line, click **Change action code**, and choose your part-sale action code.
    

1.  Choose the serial-number product (machine) the part is taken from, and enter the part's **Cost price excl. VAT** in the **Cost price for part sale** dialog. That is the value deducted from the machine and moved onto the line.
    

1.  If you want to change the machine afterwards, use the **Serial-number product for part sale** button above the lines. You can also right-click the line and choose **Open part sale** to open the serial-number product.
    

## Dispatch and invoicing

A part-sale line is not included on the dispatch note – the part is delivered as part of the invoicing. When the invoice is booked, it gets the state **Part sale processed**.

If the part sale cannot be booked, Sapera stops with the message "Part sale cannot be booked:" and a reason, for example that the serial-number product has been sold, that the cost price is higher than the serial-number product's remaining value, or that the invoice does not use stock. Fix the issue and book again.

Note: Part sale cannot be used in the Pos.

## See the part sale afterwards

Open the serial-number product, click **More** and choose **Economy overview**. The part sale appears there under the **Part sale** category and in **Income**. See [Economy overview for a serial-number product (machine economy)](https://support.sapera.io/en/articles/768.md).

* * *

**Want to know more?**

Read more in these related articles:

[

Action codes

Setup and management of action codes in Sapera — define account settings, print behavior and manufacturer/customer links, used per line on sales orders, invoices, subscriptions and order types.

](https://support.sapera.io/en/articles/88.md)[

Sales orders

Complete guide to sales orders in Financial: list view, creation, all header fields, lines, the tabs at the bottom, actions and the state machine from draft to invoicing.

](https://support.sapera.io/en/articles/81.md)[

Invoices

Complete walkthrough of the invoice overview and the invoice editor in Financial: fields, invoice lines, all actions, the state flow and the tabs at the bottom.

](https://support.sapera.io/en/articles/72.md)[

Economy overview for a serial-number product (machine economy)

Get a combined overview of what has been posted on a single serial-number product – income, costs, stock value and result.

](https://support.sapera.io/en/articles/768.md)

## Related

- [Sales orders](https://support.sapera.io/en/articles/81-sales-orders.md)
- [Click & Collect](https://support.sapera.io/en/articles/232-click-and-collect.md)
- [Shipments](https://support.sapera.io/en/articles/544-shipments.md)
- [Serial-numbered item not in stock: sale, return and buy-back](https://support.sapera.io/en/articles/639-serial-numbered-item-not-in-stock-sale-return-and-buy-back.md)
- [Claims on sales orders – link the supplier's credit note](https://support.sapera.io/en/articles/773-claims-on-sales-orders-link-the-supplier-s-credit-note.md)