Generally an individual trader must have made the automatically approved election in writing between January 1, 2011 and April 18, 2011.  The written document must have been filed (we suggest traders use certified mail with return-receipt-requested) with the IRS office where the trader normally mails his or her tax filings (attached to form 1040, 4868, 1040X etc.). Special, more liberal rules allowed certain individuals and entities such as S-corporations, Trading Partnerships and Limited Liability Companies to elect Mark-to-Market under less restrictive procedures.

At that time the written election document was not available as an IRS "form" but rather you, your tax preparer or attorney must have used a free-form format. This must have indicated: 1) an appropriate description of the election, 2) the first year that you used Mark-to-Market and 3) the specific trade or business (i.e. Schedule C) for which the election is being made.

When you change your method of accounting for gains and losses to the Mark-to-Market method you must also complete an "Application for Change in Accounting Method" form 3115. The properly completed form is then sent concurrently to both the IRS office where you normally mail your tax returns (along with form 1040) and to the national office of the IRS. The form must be filed between the dates January 1, 2012 and October 15, 2012 (we suggest that you use certified mail with return-receipt-requested).


2008/2009 changes: Under the proposed changes found in IRS Notice 2007-88 a pilot program may be started in which the form 3115 would possibly be due "by the last day of the ninth month of the requested year of change."  This could mean that rather than electing mark-to-market no later than April 18, 2011 (with a form 3115 due no later than October 15, 2012), that the date might be September 30, 2011 for both the election and the form 3115.
also see: http://findarticles.com/p/articles/mi_m6552/is_1_60/ai_n31845608/pg_5/

IRS is also clarifying (or maybe muddying the waters depending on how one looks at it) recent court decisions that challenge the concept that a request filed after the ninth month of the requested year of change (and before the next year begins) as being applicable to the succeeding year.  In other words, there will be no late filing extensions allowable under Sec 301.9100 or otherwise.