There is no off-the-shelf Acumatica app in Zapier, which stops some people before they start. It should not — Acumatica has a full contract-based REST API, and Webhooks by Zapier can drive it. The trade-off is that you handle the parts a native app would hide: authentication, endpoint calls, and the idempotency that ERP data demands.
Calling Acumatica from a Zap
To push data into Acumatica, use the Webhooks by Zapier action to call its REST endpoints. Acumatica's API is session-based — log in to get a session cookie, then reuse it — which is slightly awkward in Zapier's stateless model. The practical approach is a login call followed by the operation call within the Zap, or a small proxy service you call that manages the session. Target versioned endpoints like /entity/Default/24.200.001/SalesOrder and keep the version pinned.
Triggering a Zap from Acumatica
To react to Acumatica changes, use Acumatica business events with a webhook that POSTs to a Catch Hook trigger. When the configured event fires — an order shipped, an invoice released — Acumatica calls your Zapier URL and the Zap runs in near real time. This is far better than trying to poll Acumatica from Zapier, which is both awkward and API-costly.
Acumatica business event --POST--> Catch Hook (Zapier) -> app actions
Zap trigger -> Webhooks(login) -> Webhooks(PUT SalesOrder) --> AcumaticaAuth and idempotency are on you
Because there is no native app doing it for you, two responsibilities are yours. Handle authentication deliberately — reuse sessions rather than logging in per call, and respect Acumatica's concurrent-session limits. And make writes idempotent — check whether a record exists before creating it, because a Zap replay or a duplicate webhook must not create a second invoice. In ERP integration, a duplicate is a financial discrepancy, not a cosmetic bug.
Zapier's stateless model and lack of signature handling make session auth and verification clumsy. For anything beyond simple calls, a small proxy service between Zapier and Acumatica — managing the session, verifying webhooks, enforcing idempotency — often pays for itself. Let Zapier orchestrate and the proxy handle the ERP-specific rigor.
Zapier and Acumatica integrate cleanly despite the missing native app: Webhooks by Zapier to call the REST API outbound, Acumatica business events to Catch Hook inbound. Just own what the native app would have handled — session auth, versioned endpoints, and strict idempotency — and treat the ERP writes with the care that financial data deserves.
Independent software engineer in Nairobi specialising in Acumatica customisations, Laravel backends, and tax fiscalisation integrations across East and Southern Africa.