Version 1.6 introduces a significant number of new models to the repository. We describe the addition of 23 new models that valuably expand the portion of the phylogenetic tree covered by BiGG Models. The models include updates for four E. coli strains, S. aureus, and M. tuberculosis H37Rv and new models for five Plasmodium strains, stage specific models for Trypanosoma cruzi, C. difficile, and A. baumannii. We also expand the functionality for hosting multi-strain models, which have proven to be insightful in a variety of studies centered on comparisons of related strains. These multistrain collections are available for download on the model pages for iYL1228, STM_v1_0, and iCN718.