Microsoft Dynamics 365 Business Central and Basware integration

What moves between them

The primary flow runs from Basware into Microsoft Dynamics 365 Business Central. When an invoice finishes coding, matching, and approval in Basware and is marked waiting for transfer, ml-connector reads the accounting document with its header, lines, and coding lines, creates the matching draft purchase invoice in Business Central against the right vendor, GL accounts, and dimensions, and posts it with the bound post action. Master data flows the other way: vendors, GL accounts, and dimensions are imported from Business Central into Basware so its coding panel only offers values that exist in the ledger. Once Business Central records payment of the bill, ml-connector calls the Basware payment response callback so the invoice shows as paid on both sides.

How ml-connector handles it

ml-connector stores both credential sets encrypted and holds a Microsoft Entra ID client credentials token for the Business Central tenant, targeting the company id on the configured environment name, while on the Basware side it requests a region-specific OAuth2 bearer token, refreshing it before the roughly one-hour expiry since there is no refresh token. Work is triggered by the Basware accounting documents webhook, whose payload is verified against the X-BWAPI-Signature-256 HMAC-SHA256 header over the raw UTF-8 body before anything is processed, and a scheduled poll backs it up in case a notification is missed. Each Basware invoice is created in Business Central as a draft purchase invoice and then posted with the bound Microsoft.NAV.post action, so vendors, GL accounts, and dimensions are imported into Basware first to guarantee every coding line maps to a value that already exists in the ledger. After a successful post the connector calls the Basware transfer response callback so the document is not transferred twice, and a stable job id derived from the Basware document id deduplicates retries. Two Basware quirks are handled directly: its continuation token is returned and sent as a request header rather than a query parameter when paging, and an import that is byte-for-byte identical to the last one is silently skipped, so a real field must change to retrigger a master data record. Business Central purchase orders carry no webhook, so any PO sync is done by polling. Every record carries a full audit trail and can be replayed if a downstream call fails.

A real-world example

A mid-sized manufacturer of about six hundred staff runs Microsoft Dynamics 365 Business Central for finance and purchasing and processes several thousand supplier invoices a month through Basware. Before the integration, an AP clerk opened each approved invoice in Basware and re-keyed the header, lines, and coding into Business Central, which was slow and a steady source of posting errors, and vendors and GL accounts drifted out of sync so coders picked accounts that no longer existed. With the two systems connected, an approved invoice in Basware posts itself into Business Central against the coded vendor, accounts, and dimensions, vendor and account updates flow from Business Central into Basware automatically, and a paid bill closes out on both sides. The manual re-keying step is gone and month-end close starts from data that already agrees.

What you can do

• •Read approved and coded invoices from Basware once they are ready for transfer and post them as purchase invoices in Microsoft Dynamics 365 Business Central.
• •Confirm each handoff with a Basware transfer response so no document is transferred twice.
• •Import vendors, GL accounts, and dimensions from Business Central into Basware so coders only see valid values.
• •Send a payment response to Basware once Business Central pays the bill so the invoice closes on both sides.
• •Verify Basware webhooks by HMAC-SHA256, bridge the Entra ID and region-specific Basware tokens, and keep a full audit trail on every record.

Questions

Which direction does data move between Microsoft Dynamics 365 Business Central and Basware?

Invoices move from Basware into Business Central, where an approved and coded document becomes a posted purchase invoice. Vendors, GL accounts, and dimensions move the other way, from Business Central into Basware, so coding always references valid ledger values. Payment confirmation also flows back into Basware once Business Central pays the bill.

How does ml-connector know when a Basware invoice is ready to post?

Basware sends a signed webhook when an accounting document is approved and waiting for transfer, and ml-connector verifies the X-BWAPI-Signature-256 HMAC-SHA256 header over the raw UTF-8 body before acting on it. A scheduled poll runs alongside the webhook so an invoice is still picked up if a notification is missed. After the invoice is posted in Business Central, the connector sends a transfer response so the same document is not transferred again.

What happens to manual edits and unchanged records when master data is imported into Basware?

Basware treats imported records as managed by the integration, so a later import overwrites manual edits made in the Basware UI and there is no merge step. Business Central stays the system of record for vendors, accounts, and dimensions. Basware also silently skips an import that is identical to the last one, so a field has to actually change for a record to be reprocessed.