Current Consumer Expenditure (CE) paper diary data collection has a number of inherent drawbacks, such as limiting entry to a single individual in a single location at any given time and cumbersome portability. Additionally, having one person maintain the diary for all members of the household has additional drawbacks such as the potential for underreporting of expenditure items. The CE program is moving towards a redesign that introduces personal online diaries. A goal of this design is to leverage data collection technologies and present sampled households with options for contemporaneous data entry. Applying past experiences and lessons learned from previous online diaries, CE worked with Westat to design an optimized online diary for both mobile and desktop devices. Starting in March 2017, Westat conducted usability testing to evaluate the initial design using fully functional instruments. This presentation will provide a high-level overview of the design of the online diaries, specifically on design decisions and test procedures, as well as provide results focusing on respondent response and diary usage.