The following information is provided by Graphiq and insidegov.com:

By Alex Greer
In an effort to increase government transparency, President Barack Obama publicly the White House visitor records in September 2009 — an unprecedented decision in U.S. history. At the very least, the access records provide the name and appointment time of visitors to the White House.
While such information should shed more light on the business conducted in the White House, there are some important caveats to keep in mind. For example, the White House can choose not to disclose the names of visitors due to national security or privacy concerns. Moreover, records from Jan. 20, 2009, to September 2009 are only available if specially requested.
Nevertheless, with more than released, there’s a treasure trove of information to be mined. And did just that: We combed through the data to find 25 people who have visited the White House the most, starting from September 2009. When possible, we include each visitor’s occupation.
Most of the names on this list are from federal offices, with people from the Department of Health and Human Services, the Department of the Treasury and the Centers for Medicare and Medicaid Services showing up the most often. Interestingly, the person who visited the White House the third-most is someone we couldn’t find any information on.
#25. Chiquita N. Brooks-LaSure
Days Visited White House: 249
Position: , Center for Consumer Information and Insurance Oversight and Centers for Medicare and Medicaid Services (2012-2014)
#24. Thomas P. Maloney
Days Visited White House: 254
Position: , Office of Legislative Affairs, U.S. Treasury Department (2011-Present)
#23. Sharon N. Werner
Days Visited White House: 255
Position: , Office of the Attorney General, U.S. Department of Justice (2015-Present)
#22. Marie J. Williams
Days Visited White House: 258
Position: , U.S. Department of Agriculture (2010-2013)
#21. Jonathan M. Davis
Days Visited White House: 258
Position: , Executive Director of Strategy & Organizational Development, IRS (2008-2012)
#20. Aryana C. Khalid
Days Visited White House: 272
Position: to the Administrator for the Centers for Medicare and Medicaid Services (2012-2015)
#19. Margaret L. Richardson
Days Visited White House: 281
Position: , U.S. Department of Justice (2012-2015)
#18. Michael A. Zubrensky
Days Visited White House: 284
Position: , Office of Legal Policy, U.S. Department of Justice (2010-Present)
#17. Richard G. Kronick
Days Visited White House: 288
Position: , U.S. Department of Health and Human Services (2013-Present)
#16. William B. Schultz
Days Visited White House: 290
Position: , U.S. Department of Health and Human Services (2012-Present)
#15. David L. McClure
Days Visited White House: 292
Position: , U.S. General Services Administration (2009-2014)
#14. Mark J. Mazur
Days Visited White House: 296
Position: , U.S. Treasury Department (2012-Present)
#13. Kenneth Y. Choe
Days Visited White House: 337
Position: , Department of Health and Human Services
#12. Phyllis C. Borzi
Days Visited White House: 338
Position: , U.S. Department of Labor (2009-Present)
#11. John J. O’Brien
Days Visited White House: 345
Position: Director, Health Care and Insurance, U.S. Office of Personnel Management (2010-Present)
#10. Caya B. Lewis
Days Visited White House: 352
Position: , U.S. Department of Health and Human Services
#9. Amy J. Turner
Days Visited White House: 360
Position: , Employee Benefits Security Administration, Department of Labor
#8. Helen H. Morrison
Days Visited White House: 366
Position: , Office of Tax Policy, U.S. Treasury Department (2007-2012)
#7. Catherine E. Livingston
Days Visited White House: 372
Position: , IRS Office of Chief Counsel (2010-2013)
#6. Daniel J. Maguire
Days Visited White House: 376
Position: , Employee Benefits Security Administration, U.S. Department of Labor
#5. Cynthia R. Mann
Days Visited White House: 381
Position: , Centers for Medicare and Medicaid Services (2009-2014)
#4. Michael M. Hash
Days Visited White House: 390
Position: , Office of Health Reform, Department of Health and Human Services (2011-2014)
#3. James C. Hoff
Days Visited White House: 411
Position: Not known
#2. Marilyn B. Tavenner
Days Visited White House: 421
Position: of the Center for Medicare and Medicaid Services (2013-2015)
#1. Jason A. Levitis
Days Visited White House: 456
Position: , U.S. Treasury Department (2009-Present)