Background and Objectives: The Spectra Optia® continuous mononuclear cell (CMNC apheresis) system has emerged as the preferred device in peripheral blood stem cell collections over the original two‐step Spectra Optia® mononuclear cell (MNC apheresis) system. Until now, no comparative data were available for non‐stimulated MNC collections that are required for immunotherapy. Materials and Methods: We compared collection parameters and product composition for Spectra Optia MNC‐ as well as CMNC‐apheresis systems in non‐stimulated MNC collections from 35 registry donors intended for donor lymphocyte infusions. In a subsequent analysis, different centrifugation forces (determined as packing factor or PF) were investigated regarding target cell yield and contamination in 61 collections using the CMNC device only. Results: Comparable collection efficiencies as well as target cell yields could be achieved with the Spectra Optia MNC‐ versus CMNC program. Similar numbers of MNC, T, B and NK cells could be collected with both devices. This led to a more than twofold lymphocyte recruitment from lymphatic tissue into the blood during apheresis. However, significantly more blood had to be processed with longer procedure time using the MNC program resulting in larger product volumes compared to the CMNC setting. Red blood cell and platelet (PLT) contamination were similar. Lowering the centrifugation force from PF4·5 to PF4·0 significantly reduced PLT contamination without affecting target cell yield in the product. Conclusion: The Spectra Optia® CMNC device using lower centrifugal force (PF4·0) showed similar target cell yield and composition as well as collection efficiencies with superior performance parameters and lower PLT contamination compared to the MNC setting.