Deltek and AvidXchange integration

What moves between them

Vendor master records and the GL accounts and accounting dimensions move from Deltek into AvidXchange first, because a vendor and its coding must exist in AvidXchange before an invoice can be coded and paid. Approved AP invoices can also be submitted from Deltek into AvidXchange where the customer enters bills in the ERP rather than in AvidSuite. After AvidPay executes payment, ml-connector reads the settled payment records back from AvidXchange and posts them into Deltek as vendor payments, carrying the check number, ACH trace, or virtual card reference. Reference data is refreshed on a schedule and payment results are polled after each batch, since neither system pushes events a connector can rely on.

How ml-connector handles it

ml-connector stores both credential sets encrypted. On the Deltek side it runs the OAuth2 password grant against the customer's tenant URL and refreshes the bearer token when a call returns 401; on the AvidXchange side it sends the Company Token and User Token headers, or partner OAuth2 credentials, on every request. Deltek firms map to AvidXchange vendors, Deltek GL accounts and organizations map to AvidXchange GL codes and dimensions, and settled AvidXchange payments map to Deltek vendor payment transactions. Because neither system offers a usable push feed, GL and vendor data is synced on a schedule and AvidXchange payment and invoice status is polled after each batch. Two real gotchas shape the flow: a vendor must be pushed into AvidXchange before its invoices can clear, so vendor sync runs ahead of everything else, and Deltek has no idempotency key, so ml-connector queries Deltek by vendor number and payment number before writing to avoid duplicates. Invoice approval routing stays inside AvidSuite, so only the resulting approved or rejected status is read back, and the Deltek API user role must have full field visibility or amounts can come back as zero. Every record carries a full audit trail and can be replayed if a downstream call fails.

A real-world example

A 300-person architecture and engineering firm runs Deltek Vantagepoint for project accounting and uses AvidXchange to automate accounts payable across several offices. Before the integration, AP staff re-keyed every approved bill and its payment back into Deltek by hand, and new subconsultants and suppliers had to be set up twice, once in each system, which led to payments routed to the wrong remit-to address. With Deltek and AvidXchange connected, vendors and GL codes flow from Deltek into AvidXchange so every invoice is coded against a real project and account, and the settled check, ACH, and virtual card payments post back into Deltek automatically. The duplicate vendor setup and the manual payment entry are gone, and the project ledgers stay current.

What you can do

• •Push Deltek vendor master records into AvidXchange so every invoice routes to a real payee.
• •Sync Deltek GL accounts and organizations into AvidXchange GL codes and dimensions for accurate coding.
• •Submit approved Deltek AP invoices into AvidXchange and read their approval status back.
• •Post settled AvidXchange payments back into Deltek with check, ACH, or virtual card detail.
• •Bridge Deltek tenant OAuth2 and AvidXchange token auth, polling on a schedule with retries and a full audit trail.

Questions

Which direction does data move between Deltek and AvidXchange?

Vendors, GL accounts, and dimensions move from Deltek into AvidXchange, and approved AP invoices can be submitted the same direction. Settled payment records move the other way, from AvidXchange back into Deltek as vendor payments. AvidXchange owns payment execution, so ml-connector pulls the check, ACH, or virtual card detail back rather than initiating payments from Deltek.

Do I have to set up vendors in both Deltek and AvidXchange?

No. ml-connector pushes vendor master records from Deltek into AvidXchange so a payee exists before any invoice is coded or paid, which is required because a missing AvidXchange vendor causes a payment failure. You maintain vendors in Deltek and the connector keeps AvidXchange in step. Payment delivery method still follows the supplier's own preference in the AvidPay Network.

How does the integration handle the fact that neither system has webhooks?

Deltek only offers workflow-triggered callbacks with no signature, and AvidXchange has no public webhook system, so ml-connector runs on a scheduled poll. It refreshes vendors and GL codes on a cadence you set and polls AvidXchange for invoice status and settled payments after each batch. Because Deltek has no idempotency key, it checks each record by number before writing to prevent duplicates.