Largest companies in Ireland
The 22 companies domiciled in Ireland that trade on a US exchange, ranked by market capitalisation. Domicile comes from each company's own SEC filing, so a company headquartered here but listed only on its home market does not appear.
Combined market cap
$847.779 B
0.8% of all US-listed value
Companies
22
Ranked #9 of 55 countries
Average
$38.535 B
Mean market cap per company
| # | Name | Market cap | Close | Session | Country |
|---|---|---|---|---|---|
| 1 | Seagate TechnologySTX | $211.3B | $923.86 | +0.44% | Ireland |
| 2 | EatonETN | $170.4B | $438.76 | -0.84% | Ireland |
| 3 | AccentureACN | $122.5B | $183.52 | -0.11% | Ireland |
| 4 | Trane TechnologiesTT | $96.2B | $437.09 | -0.17% | Ireland |
| 5 | TE ConnectivityTEL | $62.1B | $214.39 | +0.43% | Ireland |
| 6 | Crh PublicCRH | $57.0B | $85.23 | -3.19% | Ireland |
| 7 | RyanairRYAAY | $28.8B | $54.69 | -2.08% | Ireland |
| 8 | Smurfit WestrockSW | $24.4B | $46.49 | +0.09% | Ireland |
| 9 | James Hardie IndustriesJHX | $15.6B | $26.85 | -1.79% | Ireland |
| 10 | Jazz PharmaceuticalsJAZZ | $15.2B | $234.88 | -2.37% | Ireland |
| 11 | Flutter EntertainmentFLUT | $15.0B | $85.89 | -3.08% | Ireland |
| 12 | IconICLR | $12.5B | $163.90 | -1.92% | Ireland |
| 13 | AlkermesALKS | $7.07B | $42.13 | -2.68% | Ireland |
| 14 | WPPWPP | $5.42B | $25.12 | -2.29% | Ireland |
| 15 | GH ResearchGHRS | $1.78B | $25.96 | -6.82% | Ireland |
| 16 | DoleDOLE | $1.22B | $12.92 | -2.12% | Ireland |
| 17 | Ads-Tec Energy PublicADSE | $824.9M | $10.98 | -0.09% | Ireland |
| 18 | AmarinAMRN | $289.8M | $13.72 | -0.22% | Ireland |
| 19 | BreraSLMT | $42.6M | $3.87 | -8.29% | Ireland |
| 20 | Fusion Fuel GreenHTOO | $16.8M | $2.23 | +12.06% | Ireland |
| 21 | SMX (Security Matters) PublicSMX | $10.5M | $9.64 | +0.73% | Ireland |
| 22 | Trinity BiotechTRIB | $5.70M | $7.01 | -5.27% | Ireland |
All 22 companies. One row per company, with secondary share classes folded into their primary listing. Updated 24 Sept 2026.
Other countries
๐บ๐ธ United States 4,029๐จ๐ฆ Canada 242๐น๐ผ Taiwan 24๐ฌ๐ง United Kingdom 75๐ฐ๐ท South Korea 12๐ณ๐ฑ Netherlands 24๐ฏ๐ต Japan 27๐จ๐ญ Switzerland 26๐จ๐ณ China 250๐ง๐ท Brazil 27๐ฆ๐บ Australia 30๐ซ๐ท France 16๐ฉ๐ช Germany 14๐ช๐ธ Spain 5๐ฎ๐ณ India 9๐ฑ๐บ Luxembourg 17๐ฎ๐ฑ Israel 117๐ฎ๐น Italy 6๐ฉ๐ฐ Denmark 7๐ฒ๐ฝ Mexico 16๐ง๐ฒ Bermuda 36๐ง๐ช Belgium 7๐ฐ๐พ Cayman Islands 31๐ฆ๐ท Argentina 14All countries โ
Figures come from SEC filings and daily market prices. Companies listed only outside the US are not covered: see methodology.