A Default Dimension is a dimension value that Business Central copies automatically onto documents and journal lines for a given customer, vendor, item or account.
A default dimension is a dimension value attached to a master record such as a customer, a vendor, an item or a G/L account. When a document or a journal line is created for that record, the value is proposed on the line without anyone typing it. Each default dimension also carries a Value Posting rule that decides whether the value can be changed, must be present, or must stay empty.
Default dimensions are stored per record rather than in one central list. Open a Customer, Vendor, Item or G/L Account card and use the Dimensions action to reach the default dimensions of that record. To apply the same default to many records at once, select several lines in a list page and use the same action. The Value Posting field offers Code Mandatory, Same Code and No Code, and leaving it empty means the value is only a suggestion.
Vendor V00030 gets a default dimension DEPARTMENT with value ADMIN and Value Posting set to Code Mandatory. On 12 March 2026 you register a purchase invoice from that vendor for CHF 1,240 of office cleaning. The header receives DEPARTMENT ADMIN automatically and the lines inherit it, so the expense lands on the administration department without any manual selection. If the item or account used on a line carries its own default for the same dimension with Same Code, the two values must match or posting stops.
The most frequent error is a posting message asking for a dimension value on a line, because Code Mandatory was set on a record that also appears on documents where that dimension is not meaningful. A second one is expecting defaults to apply retroactively: editing a vendor card does not change documents already created and never changes posted entries. Conflicting Same Code rules between a vendor and an item are the classic reason a purchase invoice refuses to post.
Before rolling out Code Mandatory across many records, post a few test documents in a sandbox, since the rule blocks posting instead of warning. When an assistant such as Zentriq Agent drafts a purchase document from a request, it picks up the dimensions coming from the default setup like any other client, and the draft still goes to a person for review and approval before posting.
A default dimension on one of the records used on the line has Value Posting set to Code Mandatory. Open the default dimensions of that customer, vendor, item or account and either supply a value or relax the rule.
No. They only apply when a new line is created. Posted entries keep the dimensions they had at the time of posting.
Zentriq's AI tools automate many of the manual processes around default dimension in Business Central. Learn about the Zentriq Agent or try Zentriq PunchOut to see how AI simplifies procurement in BC.