This report reviews estimates of fiscal impacts to the federal, state, and local governments of the foreign born who reside in the United States. By fiscal impacts, the report refers to both tax-funded expenditures for public services such as public education and public health programs, and tax revenues received through payroll withholdings on income, property taxes, sales taxes, and other taxes. The analysis of tax-funded expenditures and tax revenues together is referred to as the net fiscal impact. Congress has had a long-standing interest in the fiscal impacts of the foreign born. Congressional interest has emphasized two public policy issues: immigration policy, particularly what categories of foreign nationals and what number should be granted admission into the country; and to a lesser extent, budget concerns over the cost of public services used by the foreign born. For instance, concerns about consumption of public services by unauthorized aliens and other foreign-born persons caused Congress to pass the Personal Responsibility and Work Opportunity Reconciliation Act of 1996 (PRWORA, P.L. 104-193 ), which statutorily barred many legal permanent residents and other noncitizens from many federal assistance programs. This report focuses exclusively on literature that examines fiscal impacts of the foreign born. However, it does not address the following topics: economic impacts of the foreign born, such as their effect on industrial competitiveness, economic development, or the employment prospects, wages, and working conditions of U.S. workers; demographic impacts of the foreign born, such as their effect on the size and composition of the U.S. population; socio-cultural impacts of the foreign born, such as their effects on language use and civic participation; and environmental impacts of the foreign born, such as their effects on pollution generation, public goods consumption, and traffic congestion. Nor does it address, for the unauthorized alien population, costs to the federal government of enforcing immigration laws, such as investigating, arresting, detaining, and removing unauthorized aliens from the United States. The report examines the academic and policy literature on fiscal impacts of two populations: the entire foreign-born population and the unauthorized alien population. While many studies have been conducted to estimate fiscal impacts of just the unauthorized alien population, few have estimated fiscal impacts of just the legally residing foreign-born population. For example, The New Americans , an authoritative report discussed extensively below, considers all foreign born without analyzing populations separately according to legal status. Consequently, the first portion of this report evaluates studies of all foreign born, irrespective of legal status. The second portion evaluates studies of only the unauthorized alien population. This report is not an exhaustive review of the literature. Reviewed studies were generally selected if they included attempts to quantify the cost of public services and benefits received by the foreign born and/or tax revenues contributed, and they explained their methodologies for computing estimates. Hence, studies that applied excessively simple, incomplete, or undisclosed methodologies were generally not included. This report also excluded studies that intended to show only a favorable or unfavorable portrait of the foreign born, unless their methodological sophistication warranted their inclusion. The span of methodologies used in the analyses presented in this report ranges from basic arithmetic computations to sophisticated microeconomic and macroeconomic models. Moreover, the report distinguishes between cross-sectional studies that consider the fiscal impacts of the foreign born at a particular year, versus longitudinal studies that attempt to capture fiscal impacts of the foreign born across longer periods or several generations. With the exception of studies discussed in a 1995 General Accounting Office (GAO) report that assess fiscal impacts of the unauthorized alien population, studies reviewed herein were completed after 1996. Studies within each section are generally reviewed in chronological order, with the earliest studies evaluated first. The Appendix summarizes findings for all studies reviewed. Because of differences in research scope, methods, specific populations analyzed, and other factors, the report refrains from synthesizing these results beyond what is presented in its conclusion section. The report begins by discussing challenges of enumerating the foreign born, including the unauthorized alien population, and estimating fiscal impacts of the foreign born. Next, it reviews four sets of studies. The first, included in a National Research Council (NRC) report entitled The New Americans , represents an evaluation of short- and long-term fiscal impacts of the entire foreign-born population that served as a touchstone for subsequent research assessing the impact of U.S. immigration. The second part of this report reviews scholastic research on fiscal impacts of the total foreign-born population published after the NRC report. These scholastic analyses, published mostly in peer-reviewed academic journals, generally encompass greater analytic rigor than policy studies. The third part of this report reviews policy studies of fiscal impacts of the total foreign-born population conducted at the national and state levels that were undertaken by policy organizations. The fourth part considers the unauthorized alien population by first discussing a seminal policy debate between 1993 and 1995 assessing fiscal impacts of unauthorized aliens, and continuing with a review of policy studies conducted mostly at the state level on fiscal impacts of unauthorized aliens. Analysts have long attempted to estimate the fiscal impacts of immigrants to the United States. Their work has produced useful conceptual and analytic frameworks to guide such research. These frameworks typically describe elements necessary to produce accurate and comprehensive impact estimates: defining precisely the foreign-born population analyzed; distinguishing among the foreign born by legal status, education, decade of U.S. arrival, or other policy-relevant criteria; determining an appropriate unit of analysis for computing fiscal impacts; deciding which public service costs and tax revenues to include; making assumptions about the extent to which the foreign born use public services and contribute taxes relative to native residents; and deciding over how many generations to compute impacts. Studies can be evaluated on the extent to which they incorporate or address such elements. However, analysts face a number of methodological hurdles to incorporating these elements into fiscal impact studies. To produce viable estimates of fiscal impacts, analysts must accurately count the population of interest. The foreign born who legally reside in the United States, for instance, technically include naturalized citizens, legal permanent residents, refugees, asylees, and legal noncitizens such as temporary workers. They do not include unauthorized aliens who overstayed their legally obtained visas, violated the terms of their admission, or entered the United States unlawfully. The foreign born can be distinguished in large-scale data sets such as the Current Population Survey (CPS), the Decennial Census of the Population (Census), or the American Community Survey (ACS). However, while these data sets distinguish between foreign born who are naturalized citizens and those who are noncitizens, they do not distinguish between noncitizens with legal status and noncitizens who are unauthorized aliens. They also do not distinguish between refugee or asylee status, or between legal temporary noncitizens, such as temporary workers, and legal permanent residents. The studies reviewed in the first half of this report estimate fiscal impacts of all foreign-born persons. To evaluate fiscal impacts for only the legally residing foreign born, analysts must isolate that population from the unauthorized alien population. This can be done in several ways, including making assumptions about the legal proportion of the total foreign-born population, subtracting estimates of the unauthorized population from the total foreign-born population, or applying methodologies that assign legal or unauthorized status to a dataset's cases based on individual case characteristics and then analyzing only cases with legal status in that dataset. These methodological challenges may have contributed to the paucity of fiscal impact studies of legal immigration. Consequently, analyses of the foreign-born population's fiscal impacts sometimes yield ambiguous policy implications because they combine effects of legally residing foreign born and unauthorized aliens, two groups with distinct educational profiles and employment trajectories. Legal status also affects fiscal impacts according to federal law. For instance, whether foreign-born persons must pay taxes depends both on their legal status and if tax treaties or agreements exist between their countries and the United States. However, a foreign-born person's legal status may limit his or her eligibility to receive public services. Studies that estimate fiscal impacts of the unauthorized alien population are hampered by difficulties associated with accurately enumerating that population. People who try to avoid being detected by the government are difficult to count using formal surveys. As noted above, large nationally representative surveys that serve as primary data sources of socioeconomic information—the CPS, the Census, and the ACS—ask citizenship status but not immigration or legal status. Researchers wishing to know the cost of public services used or contribution of taxes contributed by unauthorized aliens must use alternative methods. Given the methodological challenges to accurately estimating the number, distribution, and demographic characteristics of the unauthorized alien population, researchers typically rely upon existing estimates. Much literature cites estimates of the unauthorized population produced annually by Jeffrey Passel of the Pew Hispanic Center. Most recently, the Pew Hispanic Center estimated that approximately 11.2 million unauthorized (illegal) aliens resided in the United States in March 2010. Published estimates by the Department of Homeland Security's Office of Immigration Statistics (OIS) yielded results consistent with but not equivalent to Passel's. OIS estimated that 10.8 million unauthorized aliens resided in the United States as of January 2010. Part of the difference stems from the use of different datasets: OIS uses ACS data to produce its estimates while the Pew Hispanic Center relies on CPS data. Such discrepancies suggest that attempts to quantify the fiscal impact of unauthorized aliens are hindered by disagreement over how many reside in the United States, among other factors. Producing comprehensive and realistic estimates of fiscal impacts of the foreign born requires the analyst to select which costs and revenues should be included. Most state-level analyses reviewed in this report highlighted the largest budget expenditures that varied with the size of the foreign-born population, such as public education costs, criminal justice administration costs, and the cost of public health care programs. Some studies attempted to estimate less expensive services such as sanitation and police and fire protection.