To evaluate the effect of fragmentation patterns (pie pattern versus grid pattern) on effective phacoemulsification time (EPT). Department of Ophthalmology, Goethe University, Frankfurt am Main, Germany. Retrospective case series. Eyes that had femtosecond laser-assisted cataract surgery were included. One half of the group was treated with the pie pattern. The preoperative lens density was evaluated by Scheimpflug imaging (Pentacam). Then, the eyes treated with the grid pattern were matched to the pie-pattern group based on lens density (Scheimpflug imaging). The study comprised 150 eyes (75 in the pie-pattern group and 75 in the grid pattern group). The mean patient age was 66years±10.67 (SD). The Scheimpflug density zone was 10.05%±1.52%. The mean EPT was 6.63±5.41seconds for the pie pattern, significantly higher than the 4.26±6.99seconds for the grid pattern (P<.01, Wilcoxon rank-sum test). The number of eyes with EPT=0 was significantly higher with grid pattern (37 for grid versus 1 for pie, P<.01, χ2 test). Regression analysis showed that the EPT was significantly dependent on lens density for both methods (P=.045 for pie versus P<.01 for grid). In eyes with a lens density higher than 12% (9 eyes in each group), the pie pattern showed significantly lower EPT (P=.02, Wilcoxon rank-sum test). In cases of low to moderate lens density, grid fragmentation pattern should be used because the EPT was significantly lower and a significantly higher number of eyes did not require further emulsification. However, in eyes with high density (>12%), pie-pattern fragmentation is recommended.