Missing the deadline for filing your return is serious but not the end of the world. If you asked for a filing extension, you’re not late. But if you didn’t request more time to file, don’t ignore your failure; take action now to correct the problem. Missing the deadline for filing your return is serious but not the end of the world. If you asked for a filing extension, you’re not late. But if you didn’t request more time to file, don’t ignore your failure; take action now to correct the problem. Missing the deadline for filing your return is serious but not the end of the world. If you asked for a filing extension, you’re not late. But if you didn’t request more time to file, don’t ignore your failure; take action now to correct the problem.