Taxfix: Experience Flow in Regulated Fintech

The Real Problem

When I joined Taxfix in 2020, I took over the prefill feature, a system that retrieves tax data held by the German tax office from employers, insurance providers, and health funds. The data itself was incredibly valuable for users. But accessing it required a 3-stage journey that no one understood.

• Opt-in. When the user opts in, we send a request to the tax office. The tax office sends the user a unique code via post. This typically takes 7-10 business days, but during tax season can take up to 3 weeks
• Entering the code. When the user receives their code, they enter it into the app which validates in near real-time
• Preparing the return. After 48 hours, we typically receive the user's data, after which they can start their return with prefill data

Discovering the Gap

We had an enormous amount of user research and customer service data, but nothing offering a combined view of the journey. We had no joint understanding across stakeholders of how users felt and where the pain points were. Everyone was guessing. I combined all the research together to form a picture of the current experience. The first iteration had focused on communicating the benefits of prefill and encouraging opt-in. But after hearing from users who experienced the full journey, we discovered they were confused about what happens in each stage, not unconvinced by the value.

Process

As the team was situated across the globe, I held ideation sessions with a wide range of stakeholders, developers, content designers, and tax experts, to explore how we could integrate prefill while providing the best user experience. Communication had been a key blocker before I joined. I used structured facilitation techniques to get everyone aligned.

• Affinity clustering, clearly identified the core problems in the user's prefill journey
• Crazy 8s, exposed gaps in the group's perception of the journey
• Dot voting, created consensus on approach, and when paired with a 'why,' created common understanding of the end solution
• Risk-based prioritisation, categorised every issue as 'Drop Everything,' 'Prioritise for Next Sprint,' or 'Next Available'

Key Design Decisions

Three decisions defined the outcome. First, I designed a mini-onboarding that explained the 3-stage journey with clear timeline expectations, rather than just selling benefits. Second, I implemented progressive disclosure that revealed complexity gradually, users only saw what was relevant to their current stage. Third, I shifted all stakeholder presentations from static designs to interactive prototypes, which transformed the quality of feedback. Stakeholders started thinking about the user journey, not just the visual details.

• Mini-onboarding explaining the full 3-stage prefill journey upfront
• Progressive disclosure reducing visible complexity by 60%
• Prototype-first stakeholder presentations building empathy for user journeys
• Language-aware layout system accommodating German text (20-30% longer than English)

Navigating Constraints

Working remotely from Australia with limited research resources was a challenge. I don't speak German and research had to be conducted in German. I reached out to customer service, gathered conversation data, put them on post-it notes and started clustering. Trends appeared quickly and cheaply. This became a core technique I now apply in every engagement where formal research isn't immediately available.

Results

Within a quarter, we delivered substantial improvements to the experience, most within just 3 weeks of active design work.

• 44% opt-in rate achieved in the first release
• 32% reduction in support inquiries through clearer process communication
• 13 key product improvements delivered within 3 weeks
• 5 additional feature-ready concepts queued for next quarter
• Led Sketch-to-Figma transition improving design team of 20's productivity by 40%
• Progressive disclosure pattern adopted as design system component across all teams

What I Learned

Presenting concepts in a prototype, not static mockups, transforms stakeholder feedback. It helps stakeholders build empathy for the user journey and produces higher quality feedback because they're thinking about the experience, not the pixels. And when formal user research isn't available, customer service conversation data is the fastest path to genuine insights. Cluster the conversations, and you'll see trends in hours that would take weeks to uncover through scheduled interviews.