Applied online and the HR got back around a month for a numerical and financial assessment which had to be done online within 24 hours of issue. Numerical was nothing difficult, the financial one takes some knowledge.
A few weeks later I was informed that I passed the assessments and was scheduled for an interview with the regional director and a consultant. The first interview consists of 3 parts: excel assessment (7 questions if I remembered correctly. On a paper. So you need to memorize the formulas), microteach (10min presentation. You can google to see what it is.), and a more formal interview which lasted around 45 minutes.
A week later I was scheduled for a video interview with two managers (because I am a foreigner living abroad) and after two to three days a final interview with a sales manager.
The first two interviews were more technical in my opinion. A lot of why work for FactSet and what do I know about the company, industry, their clients, competitors and finance in general. The most asked question seemed to be how would you explain what the company does to an elderly.
The third interview was more to getting to know you. The manager did not have my cv and knew nothing about me. So it seems like they want to see how you present yourself to someone new.
The interviewers were all very down to earth, polite and welcoming. It allows me to be myself and they all seemed friendly and approachable. Unlike many other companies, they test you in a way that does not stress you out. Good interpersonal skills seems to be the key here.
Overall a great interview experience.