Fortnox or Visma From an Integration Perspective?
Both Fortnox and Visma have APIs for integration, but they differ in maturity, documentation, and limitations. Which one is easiest to integrate depends on what you're building – order sync, invoice data, and payroll each carry different difficulty. The choice also affects how easily future systems can be connected.
The choice between Fortnox and Visma is usually about accounting and features. But if you’re going to connect the accounting system to other systems – the webshop, the ERP, payroll handling – there’s another question that determines how smooth day-to-day life becomes: which one is easiest to integrate? That’s the question we look at here, from a purely technical perspective and without accounting advice.
API maturity, documentation, and limitations
Both Fortnox and Visma offer APIs, meaning interfaces that let your own systems and third-party services fetch and send data. That both have an API is only the starting point, though. What determines how heavy the integration work becomes lies in the quality.
Three things are especially worth examining. API maturity – how well thought out and complete the interface is, and how well it covers the parts of the accounting system you need to reach. Documentation – how well it’s described how the API is used, which directly affects how quickly an integration can be built and debugged. And rate limits – the limits on how often the API can be called.
The last point is easily underestimated. Tight rate limits can slow down flows with large volumes, for example when many orders or invoices need to be synced in one sweep. For a small business with few transactions, it matters less; for one with high volume, it can become a bottleneck. Check the limits against your actual volumes before deciding.
Common integration cases and their difficulty
Which system is “easiest” depends on what you’re actually building. Some common cases, with a rough difficulty level:
- Order sync. Orders from a webshop or an ERP are transferred over for invoicing. Often a straightforward flow, but sensitivity increases with volume and with how much data needs to be matched correctly.
- Invoice data. Data is created automatically in the accounting system instead of being typed in by hand. Usually one of the more accessible integrations, and one of the ones that saves the most manual work.
- Payroll. Payroll-related flows are more sensitive. Here the requirements for accuracy are high and the margin for error small, which means such integrations require more care regardless of which system you’ve chosen.
The point is that the difficulty doesn’t hinge solely on Fortnox or Visma, but on which flow you’re building. A simple case can be smooth in both; a complex one requires care in both.
What the choice means for your system landscape
The accounting system rarely stays an isolated island. It tends to become a central node that other systems connect to over time – new stores, new tools, new ERPs. That’s why the consequence of the choice extends further than the first integration.
A mature, well-documented API with reasonable limits makes it cheaper and easier to connect the next system, and the one after that. A hard-to-work-with API, conversely, becomes a recurring cost every time the landscape needs to grow. The choice, then, isn’t just about the integration you’re building today, but about how easily the whole system landscape can evolve going forward.
So think one step beyond the immediate need. Don’t just ask “which one handles this sync?” but “which one makes it easiest to connect what we don’t yet know we’ll need?” That’s the question that separates a good technical choice from a short-sighted one.
How to assess it – technically and financially
From an integration perspective, the choice comes down to API quality, documentation, limitations, and how well the system fits your specific flows and volumes. That’s the assessment we make. Which system suits you best in purely accounting and financial terms is a separate question, and it should be decided together with your accountant or finance function. The decision is best when the technical and financial pictures are weighed together.
At Weapp we build integrations with both Fortnox and Visma and can assess what each API means for your specific flows. Want a technical picture before you decide? Check out our services or get in touch, and we’ll look at your integration needs.
Frequently asked questions
Do both Fortnox and Visma have open APIs?
Yes, both offer APIs that make it possible to connect your own systems and third-party services. The differences lie in the details: how mature and well-documented the API is, what limits apply to how often it can be called, and how well different parts of the accounting system are covered by the API.
What do rate limits mean for an integration?
Rate limits are caps on how many calls an integration can make within a given time. Tight limits can slow down flows with large volumes, for example when many orders or invoices need to be synced quickly. That's why it's important to check before choosing, especially for integrations that handle a lot of data frequently.
Which integrations are most common with accounting systems?
Order sync from a store or an ERP, invoice data created automatically, and payroll-related flows. The difficulty varies: a simple invoice sync is often straightforward, while flows involving payroll or advanced reconciliation are more sensitive and require more care, regardless of which system you choose.
How does the choice affect our future system landscape?
The accounting system often becomes a central node that other systems connect to. A well-functioning, well-documented API makes it cheaper and easier to add new systems over time, while a hard-to-work-with API becomes a recurring cost. The choice is therefore about more than today – it's about how easily the landscape can grow going forward.
Do you provide accounting advice for this choice?
No. We assess Fortnox and Visma from an integration perspective – API quality, documentation, limitations, and how well they fit your technical flows. Which system suits you best in accounting and financial terms is a question for your accountant or finance function, and should be weighed together with the technical picture.