To immigrate is to settle in a new country or region. To emigrate is to leave a native country or region to settle elsewhere. Obviously the words are closely related and similar enough to elicit confusion, but they’re easy to remember if you think of immigrating as arriving and emigrating as leaving. For example, someone who grew up in France and now lives in Spain emigrated from France and immigrated to Spain. Immigrate is usually followed by to, and emigrate is usually followed by from.
The distinction extends to all derivatives of the words, including emigrant, immigrate, emigration, and immigration. The em- words have to do with leaving, and the imm- words have to do with entering.
It is noteworthy that during the boom years when Ireland had close to full employment, not many chose to emigrate. [Irish Times]
The real value of American citizenship is reflected in the long and tedious ordeal legal applicants must endure to immigrate. [Arizona Republic]
Delany, for much of his life, championed emigration of blacks as a way of achieving equality, first to Central or South America, and later to Africa. [Pittsburgh Post-Gazette]
To escape torture, persecution, and societal and religious conflict, Iraqi refugees have been immigrating to America by the thousands for the last few years. [Boston Globe]