Fortnox Guide

Setting up the Fortnox Integration

To access your users' data from Fortnox, you need to enable the Fortnox integration in the Platforms Page of the Rutter dashboard.

Fortnox uses OAuth 2.0 for authentication. Enabling the integration requires a registered Fortnox developer application with a client ID, client secret, and an authorized redirect URI. You can create and manage developer integrations at the Fortnox developer portal.

User Authentication with Fortnox

A Rutter Connection is created when your end user authenticates their Fortnox account via Rutter Link. This in turn allows you to access their account data via the Rutter API.

Fortnox authentication uses the OAuth 2.0 authorization code flow. No extra fields are collected in Rutter Link — the user is redirected directly to Fortnox to log in and grant access to their company. After the user approves the requested scopes, Fortnox redirects back to Rutter, which exchanges the authorization code for an access token and a refresh token.

Fortnox access tokens are valid for one hour. Refresh tokens rotate on each use — Rutter automatically stores the new refresh token returned with every refresh response.