Conferences with sessions for undergraduates to present their research:

2014 CURM Student Research Conference
                March 14-15, 2014 at Brigham Young University, UT
Joint AMS/MAA Mathematics Meeting: there are the undergraduate research poster session and special sessions for undergraduates to give oral presentations. Also, the MAA should have travel grants of $500 for student presenters (contact Michael Dorff for more information)
                January 15-18, 2014 in Baltimore, MD
                January 10-13, 2015 in San Antonio, TX
MAA MathFest: there are special sessions for undergraduates to give oral presentations. The MAA should have travel grants of $400 for student presenters (contact Michael Dorff for more information)
                August 7-9, 2014 in Portland, OR
MAA funds Regional Undergraduate Mathematics Conferences (RUMC). Each year there are about 30 of these in the U.S. and each has funds to support regional student travel and food for both speakers and non-speakers (contact Michael Dorff for more information). It is beneficial for students to attend even if they are not giving a presentation. Here is a tentative list:
     Sept 21 or Oct 5th, 2013: Mid-Hudson Math Conf for Undergrad, Bard College, NY
     Sept 28, 2013: Shenandoah Undergrad Math and Stats Conf, James Madison Univ, VA
     Sept 28, 2013: Bluegrass Undergrad Math Symposium, Centre College, KY
     Oct 25-26, 2013: Texas Undergrad Math Conf, St. Mary's Univ, TX
     Nov 2, 2013: IL-MO Undergrad Math Conf, Southeast Missouri State Univ., MO
     Nov 8-9, 2013: Kennesaw Mountain Undergrad Math Conf, Kennesaw State Univ., GA
     Nov 8-9, 2013: Mathematics Symposium, Western Kentucky Univ, KY
     Nov 9, 2013: MAKO Undergrad Math Research Conf, Missouri State University, MO
     Mid-Late Jan 2014: Advancing Student Participation in Research Experiences Conf, Florida Gulf Coast Univ., FL
     Feb 22, 2014: YSU PME Undergrad Math Conf, Youngstown State Univ, OH
     Feb 22, 2014: Texas Oklahoma Research Undergrad Symposium, Cameron Univ, OK
     Feb 28-Mar 2, 2014: Southwestern Undergrad Math Research Conf, Mesa Community College, AZ
     Mar 8, 2014: Eagle Undergrad Math Conf 2014, Georgia Southern Univ., GA
     Mar 14-15, 2014: St. Lawrence Valley Math Conf and Competition, Clarkson Univ, NY
     Mar 28, 2014: Francis Marion Univ Regional Undergrad Math Conf, Francis Marion Univ, SC
     Apr 4-5 or Apr 11-12, 2014: Midwest Undergrad Math Symposium, Simpson College, IA
     Apr 5, 2014: Harriett J. Walton Symposium on Undergrad Math Research, Morehouse College, GA
     Apr 11-12, 2014: Rose-Hulman Conf on Undergrad Math, Rose-Hulman Univ, IN         
     Apr 12, 2014: Garden State Undergrad Math Conf, Montclair State Univ., NJ
     Apr 12, 2014: Carolinas Sports Analytics Meeting, Furman Univ., SC
     Apr 12, 2014: Math on the Northern Plains, Univ of South Dakota, ND
     Apr 26, 2014: Smoky Mountain Undergrad Conf on the History of Math, Western Carolina Univ, NC              
     Apr 26, 2014: Joint Hudson River & Spuyten Dyvil Undergrad Math Conf, Marist College, NY
Other Undergraduate Mathematics Conferences:
     Nov 8-9, 2013: Conf on Undergrad Research in Math, Penn State Univ, PA           
     Mid March, 2014: Pacific Coast Undergraduate Math Conf (PCUMC), Southern Calif.
     Beg. Aug 2014: Young Mathematicians Conf, Ohio State Univ, OH
MAA Sectional Meetings
NCUR, National Conference on Undergraduate Research
                Apr 3-5, 2014 at the Univ of Kentucky, KY
Your own university’s Undergraduate Research Day