The practical case for open borders builds upon the moral case by pointing out the many concrete benefits of open borders. These benefits mainly bolster the utilitarian case, though some of the benefits also address concerns about the libertarian case and the egalitarian case.

The practical case can be subdivided as follows.

First-order case

• Benefits to migrants: It’s largely self-evident that people who voluntarily choose to migrate anticipate some definite benefits from doing so. Empirical data backs this up very strongly. In fact, most of the gains from migration go to the migrants themselves.
• Benefits to immigrant-sending countries: There are a number of benefits that accrue to the people who choose not to migrate from countries that are sources of migrants.
• Benefits to immigrant-receiving countries: There are a number of benefits that accrue to the current residents of countries that receive immigrants.
• Global benefits: There are a number of overall benefits that are widely spread out. These include the general benefits of more efficient labor markets, greater innovation, etc. These may accrue to people in countries that are not source or target countries for migrants in any significant way.

Second-order case

• Some of the objections to open borders are overstated.
• Even in cases where there are genuine harms arising from open borders, there are cheaper ways of mitigating the harms than keeping borders closed, namely keyhole solutions (which we could also consider dealist solutions).

Miscellaneous

• Economists are generally more supportive of expanded immigration. This is significant because for many of the objections to open borders, the evaluation of these objections relies on economic analysis.
• US-specific pro-immigration arguments are additional arguments supporting immigration in the context of the United States.