On June 23, the Internal Revenue Service announced an increase in the standard mileage rate for deducting the costs of operating an automobile for business for the final six months of 2011. The rate will increase to 55.5 cents a mile for all business miles driven from July 1, 2011, through Dec. 31, 2011. This is an increase of 4.5 cents from the 51-cent rate in effect for the first six months of 2011. In recognition of recent gasoline price increases, the IRS made this special adjustment for the final months of 2011. The IRS normally updates the mileage rates once a year in the fall for the next calendar year. For more information about the new rate, visit the IRS online.