To use electronic health record (EHR) time logs and time-driven activity-based costing (TDABC) to calculate the complete cost profile of office-based fluorescein angiography (FA). Economic analysis. Patients undergoing routine FA (Current Procedural Terminology [CPT] 92235) at Vanderbilt Eye Institute in fiscal year2022. Process flow mapping for routine FA was used to define the care episode after manual observation. Deidentified time logs were sourced from the EHR and all manually validated to calculate durations for each stage. The cost of materials was calculated from internal financial figures. Cost per minute for space, equipment, and personnel were based on internal figures. Published fluorescein costs were used for base-case analysis with scenario analysis based on a range of internal figures from pharmacy quotes. These inputs were used for a TDABC analysis. Time-driven activity-based costing of FA episode of care. Secondary scenario analyses focus on breakeven scenarios for key inputs, including medication costs RESULTS: Cost analysis of office-based FA resulted in an average total cost of $152.95 (nominal) per interpreted study per patient, which was $36.52 more than the maximum Medicare reimbursement for CPT 92235 in Mac Locality for Tennessee 10312 for fiscal year 2022 ($116.43; $76.11 [technical component] and $40.33 [physician component]). The negative contribution margin is strongly influenced by the cost of fluorescein, which comprises 39.8% of the episode costs, excluding overhead. The current analysis here shows that the recently increased cost of fluorescein has driven up the cost of office-based FA relative to the current maximum allowable Medicare reimbursement, leading to a negative contribution margin and financial loss. Given conservative cost estimates here, it is unlikely for profitability to be achieved without changes in the cost of fluorescein or increased reimbursement. These results may be informative for policy discussion regarding appropriate reimbursement for codes using injectable fluorescein. Proprietary or commercial disclosure may be found after the references.