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
$851.028 B
0.8% of all US-listed value
Companies
22
Ranked #9 of 55 countries
Average
$38.683 B
Mean market cap per company
| # | Name | Market cap | Close | Session | Country |
|---|---|---|---|---|---|
| 1 | Seagate TechnologySTX | $184.2B | $812.76 | -4.71% | Ireland |
| 2 | EatonETN | $174.3B | $448.68 | +0.11% | Ireland |
| 3 | AccentureACN | $117.3B | $175.72 | +2.69% | Ireland |
| 4 | Trane TechnologiesTT | $106.1B | $482.31 | +0.76% | Ireland |
| 5 | Crh PublicCRH | $67.3B | $100.48 | +2.89% | Ireland |
| 6 | TE ConnectivityTEL | $62.6B | $216.33 | +0.58% | Ireland |
| 7 | RyanairRYAAY | $31.7B | $60.19 | -0.59% | Ireland |
| 8 | Smurfit WestrockSW | $25.3B | $48.28 | +2.88% | Ireland |
| 9 | James Hardie IndustriesJHX | $17.5B | $30.23 | +7.96% | Ireland |
| 10 | Jazz PharmaceuticalsJAZZ | $16.7B | $256.56 | -0.04% | Ireland |
| 11 | Flutter EntertainmentFLUT | $16.6B | $94.74 | +1.86% | Ireland |
| 12 | IconICLR | $12.6B | $164.51 | +2.07% | Ireland |
| 13 | AlkermesALKS | $8.25B | $49.17 | +1.65% | Ireland |
| 14 | WPPWPP | $5.94B | $27.55 | +6.17% | Ireland |
| 15 | GH ResearchGHRS | $2.08B | $30.27 | -1.21% | Ireland |
| 16 | DoleDOLE | $1.32B | $13.83 | +0.44% | Ireland |
| 17 | Ads-Tec Energy PublicADSE | $888.8M | $11.83 | +1.11% | Ireland |
| 18 | Amarin Corp Plc\UkAMRN | $303.3M | $14.36 | +0.70% | Ireland |
| 19 | BreraSLMT | $44.5M | $4.04 | -1.22% | Ireland |
| 20 | SMX (Security Matters) PublicSMX | $17.4M | $15.99 | -4.76% | Ireland |
| 21 | Fusion Fuel GreenHTOO | $17.4M | $2.43 | -0.82% | Ireland |
| 22 | Trinity BiotechTRIB | $8.39M | $12.43 | +6.79% | Ireland |
All 22 companies. One row per company โ secondary share classes are folded into their primary listing. Updated 9 Aug 2026.
Other countries
๐บ๐ธ United States 4,025๐จ๐ฆ Canada 241๐น๐ผ Taiwan 24๐ฌ๐ง United Kingdom 73๐ณ๐ฑ Netherlands 24๐ฐ๐ท South Korea 12๐ฏ๐ต Japan 26๐จ๐ญ Switzerland 26๐จ๐ณ China 250๐ง๐ท Brazil 28๐ฆ๐บ Australia 29๐ฉ๐ช Germany 16๐ซ๐ท France 14๐ช๐ธ Spain 5๐ฎ๐ณ India 9๐ฎ๐ฑ Israel 116๐ฉ๐ฐ Denmark 7๐ฑ๐บ Luxembourg 17๐ฎ๐น Italy 7๐ฒ๐ฝ Mexico 15๐ง๐ฒ Bermuda 36๐ง๐ช Belgium 8๐ฐ๐พ Cayman Islands 30๐ฆ๐ท Argentina 15All countries โ
Figures come from SEC filings and daily market prices. Companies listed only outside the US are not covered โ see methodology.