Tax Court Unanimously Rules Main Petition Deadline Is Strict

The deadline to challenge IRS tax bills at the US Tax Court can’t be extended, even in special circumstances, the court ruled Tuesday.

The court was addressing whether a deadline of 90 days for US residents—150 days for taxpayers living abroad—for challenging IRS notices of deficiency was “jurisdictional.” When a deadline is jurisdictional, the court doesn’t have jurisdiction to hear a late-filed case, no matter the reason for the lateness.

The deadline at issue, which is housed under tax code Section 6213(a), applied to more than 96% of the cases filed at the Tax ...