The aim of this study was to describe the chronic lymphocytic leukemia (CLL) patient population characteristics, treatments, outcomes, and healthcare resource utilization (HCRU) in Finland. All adult patients diagnosed with CLL (ICD-10: C91.1) and small lymphocytic lymphoma (SLL, ICD-10: C83.0) in the regions of Helsinki and Uusimaa (HUS), Southwest Finland (HDSF) and Pirkanmaa (PHD) were identified. The study focused on treated patients initiating first line treatment in 2013–2022. Treatment lines were constructed using all available medication administration and prescription data, categorized into targeted therapies, chemotherapies, chemoimmunotherapies, and other regimens. Analysis employed descriptive statistics, Kaplan-Meier for outcomes, and Sankey plots for treatment patterns. Targeted therapies were most commonly used as the first treatment line during 2018–2022, while between 2013 and 2017, the most common treatments were chemotherapy and chemoimmunotherapy. The 3-year survival rate of CLL patients in HUS, HDSF and PHD areas increased from 69% (95% CI: 64.3, 72.5) during 2013–2017 to 73% (95% CI: 66.8, 77.3) during 2018–2022. A notable proportion of patients (N = 596, 64%) had unknown del(17)p/TP53 status, and 79% (N = 740) lacked information on IGHV mutational status during the study period, despite an increase in genetic testing over time. No change in total HCRU events was observed, however a change in the types of outpatient contacts was identified over time. New treatments have been introduced as they have emerged, concurring with improved outcomes.