Tris(4-hydroxypyridinium) hydrogen sulfate–sulfate monohydrate

In the crystal structure of the title salt, 3C5H6NO+·HSO4−·SO42−·H2O, the hydrogen sulfate ion is linked to the sulfate ion by an O—H⋯O hydrogen bond. The hydrogen sulfate–sulfate anion is a hydrogen-bond acceptor for the three independent cations and the uncoordinated water mol­ecule, the hydrogen-bonding inter­actions giving rise to a three-dimensional hydrogen-bonded network. In the hydrogen sulfate–sulfate species, one of the sulfate groups is disordered in respect of its O atoms in a 2:1 ratio.