A Customer is the Business Central master record for a buyer, holding the address, posting groups, payment terms and credit limit used on every sales document.
A customer record identifies who you sell to and controls how their transactions are posted and collected. It is the anchor for sales documents, customer ledger entries and receivables reporting: one customer number carries one balance. Most of what a sales document does at posting time is decided by fields set once on this record.
Search for Customers with Alt+Q and open a card. The fields that matter most are Customer Posting Group, which decides the receivables account, Gen. Bus. Posting Group and VAT Bus. Posting Group, which combine with the item or account posting groups to decide revenue and VAT accounts, plus Payment Terms Code, Payment Method Code, Currency Code, Blocked, Credit Limit (LCY) and Salesperson Code. New records can be created from customer templates so those fields are never left empty.
Customer C00050, Alpine Retail AG, is set up with Customer Posting Group DOMESTIC, VAT Bus. Posting Group DOMESTIC, Payment Terms Code 30D and Credit Limit (LCY) CHF 25,000. Their outstanding balance is CHF 21,900 when a new order of CHF 4,200 is entered on 3 March 2026, so the total exceeds the limit and Business Central raises a credit limit warning if that check is enabled in Sales & Receivables Setup.
Wrong posting group combinations are the most common failure: posting stops with a message that a VAT posting setup or a general posting setup combination does not exist, and the fix belongs in setup, not in the document. Changing the Customer Posting Group after entries exist splits the balance across two receivable accounts and quietly breaks the reconciliation to the general ledger. Duplicate customer records for the same legal entity split the credit exposure and hide overdue amounts. The Blocked field is also misread: Blocked set to All stops every transaction on that customer, not only new orders.
Receivables work is mostly a question of asking the right list at the right time, for example customers close to their credit limit that also carry overdue invoices. Zentriq Agent answers that kind of question in plain language over your Business Central data, and if it proposes a master data change such as new payment terms, the change is a draft that a person reviews and approves in Business Central before anything is written.
The number is the key of the record, so it is not meant to change once entries exist; any renaming has to rewrite every related document and entry. In practice most teams block the old record and create a new one.
The usual causes are the Blocked field set to Invoice or All, a missing or wrong posting group combination, or a posting date in a closed accounting period. The error message names which setup combination is missing.
Zentriq's AI tools automate many of the manual processes around customer in Business Central. Learn about the Zentriq Agent or try Zentriq PunchOut to see how AI simplifies procurement in BC.