The iodite ion, or iodine dioxide anion, is the halite with the chemical formula IO−2.

Within the ion, the iodine exists in the oxidation state of +3.

Iodites (including iodous acid) are highly unstable and have been observed[1] but never isolated.

[citation needed] They will rapidly disproportionate to molecular iodine and iodates.

[2] However, they have been detected as intermediates in the conversion between iodide and iodate.