Arguments for “open borders” typically assume that migration from poorer countries to wealthy countries generally makes the migrants themselves better off; indeed, many discussions of ethics concerning immigration policy depend heavily on this assumption. But there are several grounds for wondering whether it is at least partly unfounded for economic migrants (if not for refugees), particularly if “better off” is specified in terms of happiness. Research on happiness casts doubt on the notion that increases in income contribute significantly to happiness; this article extends those doubts to the notion that one can increase happiness by gaining more income via labor migration. Certain processes (for example, adaptation, social comparisons) might work in counterintuitive ways for immigrants, perhaps inhibiting happiness despite ostensible economic gains. Arguments against immigration restrictions might therefore need to focus more on the dysfunctions of restrictions themselves and less on putative benefits to migrants from migration.