The present invention relates to extended release liquid compositions of metformin. The extended release liquid compositions are in the form of suspensions or reconstituted powder for suspensions. Said extended release liquid compositions comprise cores of metformin coated with a release-controlling agent, wherein the coated cores are dispersed in a suspension base. Said extended release liquid compositions provide the desired uniform extended release profile throughout the shelf-life of the composition. Furthermore, said extended release liquid compositions are bioequivalent to a reference composition. It also relates to processes for the preparation of said extended release liquid compositions.