How much does an API integration between business systems cost? Price guide

An API integration between two business systems typically costs €1,000–5,000. Multi-system or complex integrations run €5,000–15,000+. If that range feels too wide, it's because it is — and this post explains exactly what determines where your specific project falls.

Price tiers by integration type

Simple integration (2 systems, one-way flow): €1,000–2,500

Examples: your contact form submissions flow into a CRM, new orders from an e-commerce platform create invoices in an accounting system. One source, one destination, data flows in one direction only. These integrations are the fastest to build and the cheapest to maintain.

Bidirectional integration with conflict logic: €2,500–6,000

Both systems update the same data and you need rules to handle conflicts. Example: a product is edited in the e-commerce platform and also in the management system. Which version wins? When does a sync happen? What about concurrent edits? Building this correctly requires careful design.

Multi-system integration layer (3+ systems): €6,000–15,000+

A central integration layer connects multiple systems. Example: e-commerce → management software → CRM → email marketing, with data flowing in both directions based on events. This is closer to architecture than to "an integration" — and it's priced accordingly.

Variables that influence the cost

API quality of the systems being integrated

Modern SaaS tools (HubSpot, Shopify, Stripe) have excellent REST APIs with good documentation. Older management software sometimes has no API at all — you have to build one via database access, CSV import/export automation, or web scraping. This can double or triple the cost.

Sync frequency (real-time vs batch)

Real-time sync via webhooks is faster for the user but more complex to build robustly. Batch sync (every 15 minutes, every hour) is simpler and often enough for most business cases. The first costs 30–50% more than the second.

Error handling and retry logic

Production integrations fail sometimes: the remote API is down, the network drops, a data type has changed. A proper integration handles these cases with automatic retries, exponential backoff, dead-letter queues and alerting. Skipping this means your integration silently stops working.

Post-launch monitoring

A good integration includes dashboards showing sync status, error rates and performance. Budget 10–20% of project cost for monitoring infrastructure.

Common integrations and indicative prices

E-commerce + management software (orders + inventory + customers): €2,500–5,000
CRM + email marketing tool: €1,000–2,500
Invoicing + accounting: €1,500–3,500
Courier API for automatic tracking: €1,500–3,000
Payment gateway into a custom platform: €2,000–4,000
Multi-system layer (3+ tools): €6,000–15,000+

When to use Zapier/Make vs custom development

Zapier (€20–70/month) and Make (similar pricing) are excellent for simple workflows between SaaS tools with standard triggers. Use them when:

The integration fits inside their template library
Volume is low (hundreds of events per day, not thousands)
You don't need complex branching logic

Go custom when:

You're dealing with high volume (thousands of events per day)
Systems don't have native APIs
You need complex conditional logic
You need a level of reliability Zapier doesn't guarantee
Long-term cost of the SaaS tool exceeds a one-time custom build

Frequently asked questions

What if one of my systems doesn't have an API? Depending on the system: we can build API wrappers on top of CSV export/import, access databases directly (with the right permissions), or use web scraping. We'll tell you during analysis if and how it's feasible.

Does the integration break when a system updates? APIs rarely change incompatibly, and providers give advance notice. We monitor integrations in production and are automatically notified if something stops working. Maintenance is usually included in post-launch support.

How is sensitive data handled during sync? All communications happen via HTTPS. We don't store your customers' sensitive data in our servers — the middleware is a conduit, not an archive. GDPR-compliant documentation available on request.

Who maintains the integration long-term? The code is yours, versioned on GitHub, documented. You can keep us for maintenance or hand it to another developer. No lock-in.

These prices are indicative estimates: every project is different and the final cost depends on actual requirements. If you're exploring an integration project, check out our API integration services or tell us about your systems for a specific quote.