During the Great Famine (An Gorta Mór, 1845–1852), over 1 million died and 1.5–2 million emigrated — ~25% of pre-Famine population. Primary destinations:
| Country | Est. Arrivals | Key Ports / Regions | Notes |
|---|---|---|---|
| United States | ~1.2–1.5M | New York (Castle Garden), Boston, Philadelphia, Baltimore, New Orleans | Largest flow. Chain migration. Urban + industrial jobs. |
| Great Britain (England/Scotland/Wales) | ~300–400K | Liverpool, Glasgow, London, Manchester, South Wales | Cheapest, closest. Seasonal harvest work → permanent. Anti-Irish hostility. |
| Canada (British North America) | ~300–400K | Grosse Île (quarantine), Quebec City, Montreal, Toronto, Saint John NB | Cheaper fares (timber ships return). High mortality at Grosse Île (1847: 5,000+ deaths). |
| Australia | ~50–70K | Sydney, Melbourne, Adelaide, Hobart | Assisted passages (Earl Grey scheme: 4,000+ orphan girls). Long voyage. |
| Others | ~50K | Argentina, New Zealand, South Africa, Caribbean, US West Coast (later) | Smaller flows, specific recruitments |