Suggest the next customer account number

When to use this endpoint

Use Customer_getNextAccountNumber to reproduce the suggestion shown when a tenant enables automatic account-number assignment.

Treat the result as a suggestion only. The endpoint neither reserves it nor checks the final value again during customer creation.

Authentication and permissions

The request must authenticate with signed API-key fields or a logged-in CRM session. The handler performs no additional page or role-permission check.

The lookup and any write use the authenticated tenant; an ID from another tenant cannot be addressed through this call.

Parameters

This endpoint has no operation-specific parameters.

Example request

$next = FM_api('Customer_getNextAccountNumber');

Example response

"C010"

With no existing nonblank account numbers, the response is "1". The result is a JSON string.

Errors and unusual responses

Legacy application errors may be returned with HTTP 200. Check the decoded response for error, not only the HTTP status.

Behaviour and edge cases

• The endpoint first uses Customer_getHighestAccountNumber, so only non-deleted rows participate and its string-length ordering applies.
• It removes every digit to form a prefix, concatenates every digit into one number, increments that number, pads it to the original total digit count, then appends it after the prefix. Mixed formats can therefore be rearranged; for example AB-009Z becomes AB-Z010.
• There are no caller-controlled filters or pagination.

See it in Fieldmotion

CRM1

The legacy Create Customer dialog calls this endpoint only when customer-auto-assign-account-number is enabled, then pre-fills Account Number.

CRM2

CRM2 customer and subsidiary creation flows call the highest-number endpoint followed by Customer_getNextAccountNumber. Filter Network requests by the function name.

Related endpoints

• Customer_getHighestAccountNumber selects the source string.
• Customer_checkAccountNumberIsUnique can preflight the suggestion immediately before use.