Background In the past decades, highly innovative treatments in the field of diffuse large B-cell lymphoma (DLBCL) became available in clinical practice. The aim of this study was to assess the cost–benefit relation of third-line interventions in DLBCL from a German payer perspective. Methods Clinical benefit of allogeneic stem cell transplantation (alloSCT), chimeric antigen receptor T cells therapy (CAR T) [tisagenlecleucel (tisa-cel) and axicabtagene ciloleucel (axi-cel)] and best supportive care (BSC) was assessed in terms of median overall survival (median OS) derived from a systematic literature review in PubMed. Real-world treatment costs were retrieved from the university hospitals Cologne and Hamburg-Eppendorf. The cost–benefit relation was analysed using the efficiency frontier concept. Results Median OS varied from 6.3 months in BSC to 23.5 months in CAR T (axi-cel), while median real-world treatment costs ranged likewise widely from €26,918 in BSC to €340,458 in CAR T (axi-cel). Shown by the efficiency frontier, alloSCT and axi-cel were found as most efficient interventions. Conclusion The efficiency frontier supports the pricing of innovative therapies, such as third-line interventions in DLBCL, in relation to appropriate comparators. Yet, studies with longer follow-up periods are needed to include studies with unreached median OS and to reflect experiences gained with CAR T in clinical practice.