NOTE: This version is outdated. Please refer to the updated second version. Today, online companies are central to how Europeans access information, communicate and receive services in the digital economy. This includes platform companies such as Uber and Deliveroo in mobility and food delivery, Upwork in freelancing and Airbnb in accommodation. Yet, despite their importance, online companies are often criticised for business practices that users, workers and other businesses consider unfair, particularly because these platform participants have little choice but to accept the platforms’ rules. Fair platforms, on the other hand, are those that pay careful attention to the interests of their participants. They also create and capture value by connecting different user groups, similar to other platform companies and in line with the core elements of the platform business model. At the same time, fair internet companies prevent abuses of power. They reject practices they consider questionable and adopt alternative ways of doing business online. Building a platform based on fair business practices is complex, especially in a highly competitive environment. With this guide, we offer companies practical recommendations for making their businesses fairer towards its participants: users, workers and other businesses. Our recommendations draw on three years of research conducted within the EU Horizon project INCA – Increase Corporate Political Responsibility and Accountability (of digital platforms).