Microsoft Dynamics NAV and AvidXchange integration

What moves between them

Vendors and GL accounts flow from Microsoft Dynamics NAV into AvidXchange so invoices are coded to valid vendor and account combinations. Completed payments and payment status flow from AvidXchange back to NAV's purchase ledger on a schedule you control. New vendors created in NAV are pushed to AvidXchange automatically. GL accounts are read from NAV and mapped to AvidXchange's accounting dimension structure. Purchase invoices awaiting approval in AvidXchange are pulled into NAV for matching against original purchase orders.

How ml-connector handles it

ml-connector stores both credential sets encrypted and bridges the auth gap: Microsoft Entra ID OAuth 2.0 for NAV, and AvidXchange's proprietary token-based authentication (client credentials). It handles NAV's 3-day webhook subscription expiry by renewing before the window closes, and validates notifications via the clientState field. For entities like purchase orders not covered by NAV webhooks, ml-connector polls on a schedule. It maps NAV vendors (with vendor numbers and names) and GL accounts to AvidXchange dimensions so invoice coding lands on valid accounts. Payment data pulled from AvidXchange is matched to purchase invoices in NAV via invoice number and vendor, then posted to the purchase ledger. Retries handle transient failures on both systems, and every record carries an audit trail for reconciliation.

A real-world example

A mid-size distributor runs Microsoft Dynamics NAV for purchasing, inventory, and accounts payable. Before integration, the AP team received invoices from suppliers in email and AvidXchange, manually looked up the correct vendor and cost code in NAV, entered the invoice into AvidXchange's approval workflow, and after approval exported the payment data from AvidXchange to manually post into NAV's purchase ledger each pay cycle. With NAV and AvidXchange connected, vendors and GL accounts from NAV flow to AvidXchange automatically, so approvers code to valid accounts without NAV lookups. Approved payments flow back to NAV and post to the purchase ledger without re-entry. The AP team saves 4 to 6 hours per pay cycle.

What you can do

• •Push NAV vendors and GL accounts to AvidXchange so invoices are coded to valid vendor and account combinations.
• •Pull completed payments from AvidXchange and post them to NAV's purchase ledger on a schedule.
• •Renew Microsoft Dynamics NAV webhook subscriptions before they expire (3-day windows) to keep the sync continuous.
• •Match AvidXchange invoices to NAV purchase orders by invoice number and vendor, with a full audit trail.
• •Handle Microsoft Entra ID OAuth refresh and AvidXchange's proprietary token-based authentication on every request.

Questions

How does ml-connector handle NAV's 3-day webhook subscription expiry?

ml-connector renews NAV webhook subscriptions before the 3-day window expires, so the sync continues without manual intervention. If you disable webhooks, it falls back to polling. Notifications are validated using NAV's clientState field (not HMAC) to prevent spoofing.

Which vendor and GL account data flows from NAV to AvidXchange?

Vendor numbers, vendor names, payment terms, and posting groups flow to AvidXchange so invoices can be coded to the correct vendor. GL account numbers, descriptions, account types, and posting groups flow to AvidXchange as accounting dimensions. This ensures invoices approved in AvidXchange match valid accounts in NAV.

Can ml-connector sync purchase orders from NAV to AvidXchange?

Yes. NAV purchase orders (vendor, item, quantity, amount) are pulled from NAV and pushed to AvidXchange so the platform can match incoming invoices to purchase orders for validation. Since purchase orders are not in NAV's standard webhook list, they are polled on a schedule.