There is consensus that young patients with mantle cell lymphoma (MCL) should receive intensive immunochemotherapy regimens, but optimal treatment of elderly patients as well for as patients with limited or indolent disease is not defined. Our aim was to evaluate and compare outcome in relation to prognostic factors and first-line treatment in patients with MCL in a population-based data set. Data were collected from the Swedish and Danish Lymphoma Registries from the period of 2000 to 2011. A total of 1389 patients were diagnosed with MCL. During this period, age-standardized incidence MCL increased, most prominently among males. Furthermore, male gender was associated with inferior overall survival (OS) in multivariate analysis (hazard ratio [HR] = 1.36; P = .002). Forty-three (3.6%) patients with stage I-II disease received radiotherapy with curative intent, showing a 3-year OS of 93%. Twenty-nine (2.4%) patients followed a watch-and-wait approach and showed a 3-year OS of 79.8%. Among patients receiving systemic treatment, rituximab (n = 766; HR = 0.66; P = .001) and autologous stem cell transplant (n = 273; HR = 0.55; P = .004) were independently associated with improved OS in multivariate analysis. Hence, by a population-based approach, we were able to provide novel data on prognostic factors and primary treatment of MCL, applicable to routine clinical practice.