---
title: Units of Measure Setup
description: Define the units of measure available for items.
url: "https://theasst.com/docs/units-of-measure-setup/"
updated: "2026-10-06"
category: Setup / Company
---

# Units of Measure Setup

Units of Measure defines the unit choices available on every [Item's](https://theasst.com/docs/item-info/) **Unit of measure** field.

![Units of Measure list with Each, Hour, Month, and Ton, reorderable](https://theasst.com/wp-content/uploads/2026/09/uom.webp)

Every company starts with four defaults -- **Each**, **Hour**, **Month**, and **Ton**. Add your own by typing into a blank row, reorder with the arrows, and click **Save Changes**.

## Using the List

- Type a name into a blank row to add a unit; a new blank row appears below it.
- Use the arrows to reorder. The first unit is the default for new lines, so put your most common one first.
- Click the red X to remove a unit.
- Nothing is saved until you click **Save Changes**.

## Where Units Are Used

The **Unit of measure** on an [Item](https://theasst.com/docs/item-info/), and the **UoM** column on every line of a [quote](https://theasst.com/docs/quotes/), [order](https://theasst.com/docs/sales-service-orders/), [invoice](https://theasst.com/docs/invoices/), [purchase order](https://theasst.com/docs/purchase-orders/), and [bill](https://theasst.com/docs/bills/). Units named *Hour* or *Day* are special: on a Service line they unlock the Started/Ended times and the [Rate type](https://theasst.com/docs/service-rate-rules/), so keep those names if you bill by time.