- October 15 – Filing deadline for 2012 individual tax returns on automatic six-month extension of the April 15 deadline.
- October 15 – If you converted a regular IRA to a Roth in 2012 and now want to switch back to a regular IRA, you have until October 15, 2013, to do so without penalty.
October 1 was the original deadline for employers to provide their workers with a notice about the state health insurance exchanges created by the Affordable Care Act. Failure to comply could have resulted in fines of up to $100 per day. The U.S. Department of Labor recently announced that, while companies are required to provide the notice, there will be no fine or penalty under the law for failure to do so.