The disclosure relates to poly alpha-1,6-glucan ether compounds comprising poly alpha-1,6-glucan substituted with at least one positively charged organic group and having a degree of substitution of about 0.001 to about 3.0. The poly alpha-1,6-glucan comprises a backbone of glucose monomer units wherein greater than or equal to 40% of the glucose monomer units are linked via alpha-1,6 glycosidic linkages, and optionally about 3% of the backbone glucose monomer units have branches via alpha-1,2 and/or alpha-1,3 glycosidic linkages. Compositions comprising a poly alpha-1,6-glucan ether compound can be useful in various applications.