Question: how often do you need to renew your itin number?
Answer: Taxpayers who have not used their ITIN to file a federal return at least once in the last three years will see their number expire Dec. 31, 2017. ITINs with middle digits 70, 71, 72 or 80 will also expire at the end of the year. These taxpayers should renew their ITIN if they will have a filing requirement in 2018.