John and Martha are planning to be married. Both are professionals each with gross incomes of $100,000 annually. They are deciding on a wedding date. They have two dates to choose from: December 14, 2013, or January 11, 2014. If they marry on December 14, 2013, they will have to choose between married filing separately and married filing jointly. They will both claim the standard deduction. Is there an advantage to either method of filing? If they postpone their wedding until the January date and file as single persons, will they reduce their tax bill for 2013? Please include how you calculated it step-by-step.