Units of measure in Business Central: base, sales and purchase units
Units of measure in Business Central control how you count, buy, sell and store an item. For example, you might buy by the pallet, stock by the piece and sell by the box. Every item has one base unit and as many other units as it needs. Each one has a conversion quantity. This guide covers the setup and the choices that are hard to undo.
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Start your units of measure in Business Central with the list
The Units of Measure page is a simple company-wide list of codes and descriptions, such as PCS, BOX, KG and HOUR. Keep it short and clear. Two codes with the same meaning, such as EA and PCS, confuse people on item cards. Later, they confuse your reports too.
Each code can carry an international standard code. That matters when you swap electronic documents with trading partners, because their systems expect the standard code, not your own short form. You can also translate descriptions per language. Then a customer abroad reads the unit in words they know.
Clean up your unit codes →
- ✓One code per real unit
- ✓Clear descriptions
- ✓International standard codes
- ✓Translations where needed
- ✓No near duplicates
How the base unit of measure in Business Central works
On the Item Card, Base Unit of Measure is the unit you use to record stock. Item ledger entries, inventory quantity, unit cost and planning all use it. You may enter a document in boxes. Even so, the ledger stores the equivalent in the base unit.
Choose the smallest unit you will ever need to count, move or sell. If you keep stock in boxes and a customer later wants single pieces, you end up with fractions. Once an item has ledger entries, changing its base unit is not practical. The usual answer is a new item number.
Get base units right →- ✓Inventory quantity on hand
- ✓Unit cost and valuation
- ✓Reorder point and planning
- ✓Physical inventory counts
- ✓Item ledger entries
Item units of measure in Business Central and conversions
From the item card, open Item Units of Measure. The page lists the base unit with a quantity of one. Add each other unit and enter Qty. per Unit of Measure, the number of base units it holds. For example, a box of twelve pieces, or a pallet of forty boxes written in pieces.
The same page holds length, width, height, cubage and weight for each unit. Warehouse functions and shipping integrations can use them. Conversions belong to the item, not to the code. So a box can mean twelve of one item and six of another. Check each new item with that in mind.
Check your conversions together →- ✓Quantity per base unit
- ✓Height, width and length
- ✓Weight of the unit
- ✓Cubage for bin capacity
- ✓Rounding precision
Sales and purchase units of measure in Business Central
Two more fields on the item card, Sales Unit of Measure and Purch. Unit of Measure, set the default unit on document lines. A buyer who always orders pallets sees pallets. A sales team that quotes in boxes sees boxes. Either person can still override the unit on a line.
Prices and costs follow the unit. A sales price list line can name a unit of measure code, so the box price is not simply twelve times the piece price. Item references can carry a unit too. That way, a scanned barcode on a carton fills in both the item and the right unit.
Set up pricing by unit →- ✓Sales price list lines
- ✓Purchase price list lines
- ✓Item references and barcodes
- ✓Warehouse put-away unit
- ✓Production and assembly BOMs
Rounding and units of measure in Business Central pitfalls
Conversions that do not divide evenly leave tiny remainders. Say you sell a case of three one at a time. The base quantity then shows a recurring decimal, and stock that should read zero shows a fraction. The Qty. Rounding Precision field on the item unit of measure tells Business Central how to round the base quantity.
Other problems come from data, not from the system. You might copy conversion quantities from an old system without checking them. A supplier might change a pack size while the item keeps its old factor. Or different departments might use one unit to mean different things. Each of these leads to wrong stock figures.
Ask us about rounding →- ✓Base unit set too large
- ✓Uneven conversion factors
- ✓Pack sizes changed by vendors
- ✓Unchecked migrated conversions
- ✓Missing rounding precision
Questions on units of measure in Business Central
Can the base unit of measure be changed later?
Not in any practical way once the item has entries or open documents. The reliable route has four steps. First, create a new item with the correct base unit. Next, move the old stock across with item journals or a reclassification. Then block the old item. Finally, update any open documents and price lists. That keeps your history clean.
Can one item be sold in several units?
Yes. You can pick any unit listed on the item's units of measure page on a sales line. Business Central converts the quantity to the base unit behind the scenes. The default comes from the Sales Unit of Measure field on the item card. So a customer can order by the box today and by the piece tomorrow. The stock figure stays right either way.
How do catch weight items work?
Standard Business Central records one quantity per entry and converts it by a fixed factor. So true catch weight, where each piece has its own weight, does not come built in. Food and process companies usually add an AppSource solution designed for it. We can help you compare those options and test one against your own items.
Do resources and services use units of measure too?
Yes. Resources have their own resource units of measure, typically hour and day, with a conversion between them. Business Central prices and costs time in those units. Lines for G/L accounts and charges on documents can also carry a unit code for printing. So the same idea of a clear unit list helps outside inventory as well.
Does a unit of measure affect item costing?
Business Central keeps unit cost per base unit. When you enter a purchase line in another unit, the direct unit cost on the line is for that unit. The system converts it on posting. Reports and valuation then work in the base unit throughout. So a wrong conversion quantity gives a wrong cost, not just a wrong count.
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