Purpose: We examine the methodological and economic policy implications of three operationalizations of retirement migration. Design and Methods: We compared the traditional age-based definition of retirement migration and two retirement-based definitions, based on degree of labor-force participation and retirement income, by using the 2000 U.S. Census Public Use Microdata Sample. Results: The age-based definition overestimated the number of retired migrants, although the ranking of host and donor states remained relatively stable; nevertheless, states revealed different rates of change in inmigration and outmigration and income streams declined. Implications: Retirement-based definitions are more useful and precise for those researchers considering the economic implication of retirement migration.