Retirees, go west. In WalletHub’s annual list of best states for retirement, states west of the Mississippi had a better showing this year.

WalletHub rated states based on 24 metrics in three key areas: affordability, quality of life and health care. Data was pulled from various sources, including the U.S. Census Bureau, the FBI, the Bureau of Labor Statistics, the Centers for Disease Control and Prevention, the Centers for Medicare and Medicaid Services, and WalletHub’s own research.

Affordability was the primary determinant in judging a state’s friendliness to retirees, particularly cost of living. Taxes on pension and Social Security income, and WalletHub’s own Taxpayer ranking, as well as the annual cost of in-home services, were also considered.

However, affordability isn’t the only factor that goes into that decision. Proximity to friends and family, geography and climate, availability and access to health services, local and regional culture, crime statistics, recreation and leisure opportunities, tax burden, and political climate and employment prospects are all critical factors in choosing where to live after retirees stop working, according to Steven Applewhite, professor emeritus in the Graduate College of Social Work at University of Houston.

And while Olivia Mitchell, director of the Boettner Center for Pensions and Retirement Research in the Wharton School at University of Pennsylvania, said many people fail to take into account their new state’s income tax rate and tax base, or whether their pension or Social Security income will be taxed, Scott Baker warned that just looking at retirees’ future tax burdens isn’t enough. “Differences in lifestyle and living expenses could easily swamp the financial benefits of a zero percent state income tax rate,” Baker, the assistant professor of finance in the Kellogg School of Management at Northwestern University, said in the report.

(Related on ThinkAdvisor: 10 Best States for Retirement: 2015)

Retirees should also question whether they want to move at all. “Many retirees today may choose not to settle elsewhere upon retirement but rather to ‘age in place,’ meaning they will remain in their homes as they enter their later years,” Applewhite said in the report.

Here are the 15 best states for retirees, as rated by WalletHub.

Golden Gate Bridge in San Francisco. (Photo: AP)

15. California

  • Total Score: 59.01
  • Affordability Rank: 41
  • WalletHub Taxpayer Rank: 8
  • Quality of Life Rank: 1
  • Health Care Rank: 13

Saint Louis Gateway Arch.

14. Missouri

  • Total Score: 59.07
  • Affordability Rank: 23
  • WalletHub Taxpayer Rank: 30
  • Quality of Life Rank: 20
  • Health Care Rank: 22

Bikers in Des Moines. (Photo: AP)

13. Iowa

  • Total Score: 59.86
  • Affordability Rank: 29
  • WalletHub Taxpayer Rank: 43
  • Quality of Life Rank: 19
  • Health Care Rank: 8

Civil War Museum in Harrisburg. (Photo: AP)

12. Pennsylvania

  • Total Score: 60.41
  • Affordability Rank: 22
  • WalletHub Taxpayer Rank: 39
  • Quality of Life Rank: 5
  • Health Care Rank: 32

(Related on ThinkAdvisor: 10 Best States for Retirement: 2015)

Grand Canyon in Arizona. (Photo: AP)

11. Arizona

  • Total Score: 61.01
  • Affordability Rank: 19
  • WalletHub Taxpayer Rank: 15
  • Quality of Life Rank: 13
  • Health Care Rank: 19

Virginia Beach Boardwalk and Bike Path.

10. Virginia

  • Total Score: 61.06
  • Affordability Rank: 15
  • WalletHub Taxpayer Rank: 28
  • Quality of Life Rank: 14
  • Health Care Rank: 31

(Related on ThinkAdvisor: 10 Best States for Retirement: 2015)

Fremont Street in Las Vegas. (Photo: AP)

9. Nevada

  • Total Score: 61.19
  • Affordability Rank: 8
  • WalletHub Taxpayer Rank: 5
  • Quality of Life Rank: 12
  • Health Care Rank: 43

Tipi on a Montana Lake.

8. Montana

  • Total Score: 61.39
  • Affordability Rank: 21
  • WalletHub Taxpayer Rank: 3
  • Quality of Life Rank: 22
  • Health Care Rank: 10

River Walk in San Antonio. (Photo: AP)

7. Texas

  • Total Score: 61.85
  • Affordability Rank: 9
  • WalletHub Taxpayer Rank: 29
  • Quality of Life Rank: 16
  • Health Care Rank: 40

Great Big Idaho Potato Truck in Boise.

6. Idaho

  • Total Score: 62.19
  • Affordability Rank: 10
  • WalletHub Taxpayer Rank: 7
  • Quality of Life Rank: 32
  • Health Care Rank: 29

Red Rocks Park in Colorado.

5. Colorado

  • Total Score: 62.23
  • Affordability Rank: 27
  • WalletHub Taxpayer Rank: 12
  • Quality of Life Rank: 6
  • Health Care Rank: 11

(Related on ThinkAdvisor: 10 Best States for Retirement: 2015)

Myrtle Beach Boardwalk (Photo: AP)

4. South Carolina

  • Total Score: 62.5
  • Affordability Rank: 6
  • WalletHub Taxpayer Rank: 9
  • Quality of Life Rank: 26
  • Health Care Rank: 34

The Corn Palace in Mitchell, South Dakota. (Photo: AP)

3. South Dakota

  • Total Score: 66.62
  • Affordability Rank: 14
  • WalletHub Taxpayer Rank: 16
  • Quality of Life Rank: 29
  • Health Care Rank: 1

A rider in the Tour de Wyoming. (Photo: AP)

2. Wyoming

  • Total Score: 67.09
  • Affordability Rank: 1
  • WalletHub Taxpayer Rank: 4
  • Quality of Life Rank: 28
  • Health Care Rank: 16

Miami Skyline. (Photo: AP)

1. Florida

  • Total Score: 70.75
  • Affordability Rank: 2
  • WalletHub Taxpayer Rank: 10
  • Quality of Life Rank: 3
  • Health Care Rank: 15

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