MYOB and AvidXchange integration

What moves between them

Invoices and purchase orders flow from AvidXchange into MYOB as bills or purchase orders, mapped to the vendor and GL account that match the AvidXchange coding. Payment confirmations flow from AvidXchange back into MYOB as supplier payments, posting to the same GL accounts. The sync runs on a schedule you control, typically after each approval cycle in AvidXchange or at end of day, and ml-connector does not write approved invoices back into AvidXchange since AvidXchange is the system of record for AP workflow.

How ml-connector handles it

ml-connector stores your AvidXchange OAuth credentials and your MYOB company file token encrypted and refreshes each as they expire. On the MYOB side, it handles the three-part authentication requirement (OAuth Bearer token plus company file username and password in the x-myobapi-cftoken header) and retries any call that returns 401. Invoices from AvidXchange are matched to MYOB vendors by name or ID, and GL codes are mapped to matching MYOB GL accounts before posting. Because both APIs enforce rate limits (MYOB at 8 requests per second, AvidXchange via the partner portal), ml-connector spaces requests and backs off on HTTP 429, and it stores the MYOB RowVersion on each record to avoid 409 conflicts on updates. Every invoice and payment carries a full audit trail and can be replayed if a downstream GL post fails. The flow polls at a cadence tied to your approval process rather than waiting for a push.

A real-world example

A mid-sized Australian business uses MYOB for accounting and cost center allocation across multiple locations, and AvidXchange for invoice approval and payment execution across the company. Before the integration, the finance team exported approved invoices from AvidXchange daily, manually coded them to the correct MYOB GL accounts and cost centers by reference to a spreadsheet, and entered them into MYOB by hand. Month-end close involved reconciling which invoices AvidXchange had approved but MYOB had not yet recorded, and supplier payment statements rarely matched GL balances. With MYOB and AvidXchange connected, approved invoices flow into MYOB automatically, coded and ready to post, and payment confirmations keep the cash accounts in sync. The manual coding step is gone and month-end close no longer requires a separate invoice reconciliation.

What you can do

• •Sync approved invoices and purchase orders from AvidXchange into MYOB, matched to the correct vendor and GL account.
• •Post supplier payments from AvidXchange back into MYOB as purchase payments, updating cash and GL balances.
• •Map AvidXchange GL codes and accounting dimensions to MYOB GL accounts so invoices land on the correct accounts.
• •Authenticate AvidXchange via partner OAuth and MYOB via OAuth2 plus company file credentials, with automatic token refresh.
• •Poll on a schedule tied to your approval cycle, with retries on rate limit hits and a full audit trail on every invoice and payment.

Questions

Do invoices flow only from AvidXchange into MYOB, or both directions?

Invoices flow from AvidXchange into MYOB. AvidXchange is the system of record for invoice approval, workflow routing, and payment execution, so ml-connector does not write invoices back into AvidXchange. Payment confirmations flow back from AvidXchange to MYOB so your cash accounts stay in sync.

How does ml-connector handle MYOB's three-part authentication and 20-minute token expiry?

ml-connector stores your OAuth Bearer token, API Key, and company file credentials encrypted and refreshes the Bearer token before expiry. Every request includes the correct x-myobapi-cftoken header with the company file username and password in Base64 format. If MYOB returns 401, ml-connector re-authenticates and retries the call.

What happens when AvidXchange or MYOB rate limits a request?

ml-connector detects HTTP 429 responses, backs off with exponential delay, and retries the request. Because MYOB enforces 8 requests per second and AvidXchange limits requests per the partner portal agreement, ml-connector spaces requests to stay under both limits and logs the delay in the audit trail so you can see when throttling occurred.