Connecting Exact Online with n8n: how an Exact Online integration that you own works
An Exact Online integration with n8n makes your web shop or another system exchange data with your accounting automatically: orders go into Exact, products and prices come back. n8n does the work, a database of its own remembers what has been processed and monitoring tells you in plain language when something goes wrong.
I build these integrations self-hosted, on a server that belongs to the client. On this page I explain how it works, why I do not use an off-the-shelf app, what it costs and who looks after the integration afterwards. It is a deeper look at business process automation. No sales talk.
Updated on 15 October 2026. Reading time about 5 minutes.
On this page: what it does · how it works · where it goes wrong · why not an app · cost · ownership · when not · API facts · questions
What does an Exact Online integration with n8n do?
It keeps two systems in step without anyone retyping. A web shop and an accounting package each work fine, but know nothing about each other. Without an integration, every order has to be entered in Exact by hand and every price change has to be copied to the web shop by hand. That works until it gets busy.
In practice it comes down to three things:
- Orders go from the web shop to Exact Online.
- Products and prices go from Exact to the web shop. Exact stays in charge.
- Token management keeps access to the Exact API working without anyone having to log in again.
A fourth part is often forgotten: monitoring. Without it, you only find out the integration has stopped when a customer calls. More kinds of integrations are listed under integrations.
How does an Exact integration with n8n work?
n8n runs as a middle layer on a server of its own. Workflows fetch data from one system, convert it and write it to the other. Every workflow follows the same steps:
- Trigger. A new order or a fixed time starts the workflow.
- Check. An integration database remembers what has been processed, so nothing lands in Exact twice.
- Write. The workflow reads or writes through the Exact API.
- Error handling. If Exact returns an error, the workflow tries again. If that still fails, the message goes into a queue.
- Failure e-mail. Every deviation sends an e-mail to a person, with three headings: what went wrong, what it means and what has to happen.
For Mercabilis, a web agency, this runs on a server of its own in Europe with Cloudflare in front. On it run nine workflows (four active) and an integration database of twelve tables (as of October 2026). What that looks like is in the Mercabilis case.
Where does an Exact integration go wrong?
Mostly not in the integration itself, but because the system on the other side does not respond for a moment or a piece of data is missing. Three examples you must be able to absorb:
- Exact returns a server error. It happens now and then at night. The integration waits and tries again.
- A product code is missing. An order then cannot land in Exact. The failure e-mail names the order number and the product code, so someone can fix it in a minute.
- Access expires. Exact works with short-lived tokens. If a renewed token is not stored properly, the integration stops. That is why token management is part of the integration.
Note: no failure e-mail can mean that everything is fine, or that the monitoring itself has stopped. So also check that the monitoring heartbeat is present.
Why not an off-the-shelf app?
Because with an off-the-shelf app you cannot see what is happening, and when it fails you usually hear about it from your customer. An app runs on someone else’s server. That can work fine, but you give up three things:
- Ownership. With me, the server and accounts are in the client’s name. If the cooperation ends, the integration stays yours.
- Readability. All the logic is in n8n workflows that you can read and export. Someone else can take them over.
- Monitoring. The integration reports on itself, in plain language, to whoever needs to know.
That was also Mercabilis’s reason for not choosing an integration plugin. The trade-off is worked out in the case.
What does an Exact Online integration cost?
The price depends on the number of flows and integrations. I do not name an amount here; you hear it before the assignment, not after.
The pricing page lists the parts: the secure n8n set-up (server, access, backups, monitoring), the integration itself, which starts as a quick win with one process, and maintenance as a fixed monthly package.
Also count the hours of your own people during the build. They have to test and explain how Exact is set up at your company.
Who owns the integration and who maintains it?
The integration belongs to the client. The server and accounts are in the client’s name, the workflows can be exported and when maintenance ends you receive the documentation.
Maintenance is a fixed monthly package. It includes checking that the Exact token is valid, that the workflows are active, that the heartbeat is present and that a backup exists that can be restored. You get a short monthly report. In case of a failure I respond within 24 hours on working days. That is a response time, not a guaranteed fix time, and the agreement says so too.
When is an integration of your own too much?
When you have few orders, standard fields and no exceptions. Then an off-the-shelf app is often enough and you save the cost of a server of your own.
An integration of your own pays off when the integration is business-critical, when there are exceptions or when you want to know what is happening. Not sure? Book a scan; the outcome may well be no.
Facts about the Exact Online API
Checked on 2 November 2026 against Exact's official documentation. Limits, prices and versions change; the source is listed per row.
| Fact | What the documentation says | Source |
|---|---|---|
| Authentication | OAuth 2.0 with authorization code. You register an internal app yourself in your own administration (Import/Export, App registrations) with a public HTTPS redirect URI. External apps for multiple customers require an Exact Online Developer subscription. | Exact: OAuth authorization |
| Token lifetime | Access token 10 minutes; a new token may only be requested after 9.5 minutes. Refresh token 30 days and single-use; after use you receive a new refresh token. | Exact: OAuth step 3 |
| Rate limits | 60 calls per minute and 5,000 per day per administration per app; parallel calls are not allowed. When exceeded, 429 with X-RateLimit headers. At most 10 errors per hour per endpoint, otherwise a temporary block. | Exact: API limits |
| Webhooks | Yes, per topic (Accounts, Items, StockPositions and more). The message only contains IDs and an HMAC-SHA256 hash; ten retries over about 34 hours. The FinancialTransactions webhook was replaced in June 2026 by webhooks per entry type. | Exact: Webhooks |
| Test environment | A demo administration through a trial account and a test app through the App Store. | Exact: Getting started |
| Version and deprecations | REST API v1 with single, Bulk and Sync endpoints; Exact recommends the Sync endpoints. Announced: custom GUIDs through REST no longer possible (July 2026), InvoiceSalesOrders mandatory (October 2026), a selection of XML APIs deprecated from January 2027. | Exact: Breaking changes |
| API cost | You register an internal app within your own subscription. Higher limits (30,000 per day) only with Exact Online Premium. | Exact: Register an app |
| n8n | No built-in node; community nodes on npm, the latest from December 2025. I connect through the API with an HTTP step. | n8n documentation |
What you need on your side
- An Exact administrator who registers an app in your administration with a public HTTPS redirect URI
- The division code of the administration and the user's consent for that administration
- A demo administration to test against before production is touched
- Item codes and VAT codes in Exact that match your web shop
What I do not do
- I do not make parallel calls; Exact does not allow them and blocks you if you do.
- I do not request a new token every few minutes; the integration stores the token and renews it exactly on time.
- I do not build on the XML APIs that Exact deprecates from January 2027.
Frequently asked questions about an Exact Online integration
What is an Exact Online integration?
A connection between Exact Online and another system, such as a web shop, so that data flows both ways automatically. Orders arrive in Exact, products and prices go back to the web shop.
Does this also work with a web shop other than WooCommerce?
Yes. The web shop is the easiest side to replace. The hard side is monitoring, token management and error handling, and those do not depend on the web shop system.
What happens when Exact Online does not respond for a moment?
The integration waits and tries again. If that still fails, a failure e-mail in plain language follows. So you do not have to ask whether the integration is still running.
Can I build an Exact integration myself with n8n?
A simple integration is possible, with some learning. Token management, error handling and monitoring make it skilled work. The mistake that happens most often: it works, but nobody sees it when it stops.
Who owns the integration?
The client. The server and accounts are in the client’s name and the workflows can be exported. More about this is in the Mercabilis case.
Want to know whether an integration of your own pays off for you?
Book a free scan. I work through one integration with you and you get a short report with figures, even if the answer is no.
Stefan de Graaf has been building automations since 2021, first for his own web shops and since 2026 for other small businesses under the name AIAgentCycle. He works from Oosterwolde, Friesland. More about Stefan.