Largest Listed Companies in Ireland by Market Capitalization
Euronext Dublin traces its origins to 1793, making it one of the oldest stock exchanges in Europe. Originally known as the Irish Stock Exchange, it was acquired by Euronext in 2018 and currently lists around 37 companies across four market segments, including Euronext Dublin, Euronext Growth, the Global Exchange Market, and the Atlantic Securities Market.
The main benchmark is the ISEQ 20, a free-float market capitalisation-weighted index that tracks the 20 most liquid and largest companies on the exchange. It is reviewed quarterly, with constituent weightings capped at 20%.
Despite the relatively small number of listed companies, Ireland’s equity market punches above its weight thanks to firms with major global operations:
- Industrials – Building materials & packaging: CRH plc (operating in over 30 countries), Kingspan Group (high-performance insulation), and Smurfit WestRock (the world’s largest listed packaging company).
- Industrials – Aviation: Ryanair Holdings, Europe’s largest low-cost airline, and AerCap Holdings, a leading aircraft leasing firm.
- Financials: AIB Group and Bank of Ireland, the two largest domestic banks.
- Consumer Discretionary: Flutter Entertainment, the Dublin-headquartered sports betting group behind brands like Paddy Power, Betfair, and FanDuel.
- Consumer Staples & Healthcare: Kerry Group (taste and nutrition solutions) and ICON plc (contract research).
All shares on Euronext Dublin trade in EUR. The exchange closed its physical trading floor in 2000 and now operates electronically via ISE Xetra, a platform provided in partnership with Deutsche Börse. Many of Ireland’s largest listed companies also maintain listings on the London Stock Exchange or the NYSE, reflecting their international reach.
Regulated brokerThe table below ranks the largest Irish publicly traded companies by market capitalization, with live data updated regularly.
| Symbol | Stock | Price | Change % | Chart (24H) | Marketcap |
|---|---|---|---|---|---|
| ACN |  Accenture ACN | $265.16 | 0.34% | 156.64B | |
| ETN |  Eaton ETN | $327.02 | 7.38% | 127.05B | |
| MDT |  Medtronic MDT | $104.84 | 0.11% | 134.10B | |
| TT |  Trane Technologies TT | $392.43 | 4.40% | 85.90B | |
| CRH |  Cement Roadstone Holding CRH | $95.45 | 3.39% | 63.50B | |
| JCI |  Johnson Controls JCI | $131.46 | 6.45% | 79.63B | |
| EXPGF | Experian EXPGF | $42.30 | 1.95% | 37.05B | |
| IR |  Ingersoll Rand IR | $81.85 | 2.77% | 31.43B | |
| FLUT |  Flutter Entertainment FLUT | $82.97 | 1.44% | 14.43B | |
| RYAAY |  Ryanair RYAAY | $58.53 | 0.88% | 30.31B | |
| ICLR | ICON plc ICLR | $201.65 | 0.72% | 15.11B | |
| APTV |  Aptiv APTV | $40.85 | 5.57% | 8.27B | |
| STE |  Steris STE | $254.12 | 2.50% | 24.78B | |
| STX | Seagate Technology STX | $466.53 | 16.25% | 107.10B | |
| AER | AerCap AER | $166.17 | 0.27% | 25.24B | |
| KRX.IR |  Kingspan Group KRX.IR | €93.65 | 0.27% | 17.09B | |
| JHX | James Hardie Industries JHX | $28.66 | 2.91% | 16.64B | |
| KRZ.IR | Kerry Group KRZ.IR | €97.95 | 2.83% | 15.57B | |
| A5G.IR | AIB Group (Allied Irish Banks) A5G.IR | €11.27 | 2.26% | 23.59B | |
| BIRG.IR |  Bank of Ireland Group BIRG.IR | €18.94 | 1.76% | 17.86B | |
| ALLE | Allegion ALLE | $187.14 | 2.88% | 15.91B | |
| JAZZ | Jazz Pharmaceuticals JAZZ | $227.32 | 3.13% | 14.59B | |
| DCC.L |  DCC plc DCC.L | GBp6,455.00 | 0.08% | 5.52B | |
| GL9.IR |  Glanbia plc GL9.IR | €19.54 | 7.92% | 4.72B | |
| PRGO |  Perrigo PRGO | $15.71 | 0.76% | 2.18B | |
| ALKS | Alkermes ALKS | $44.54 | 2.94% | 7.48B | |
| ADNT | Adient ADNT | $17.07 | 0.70% | 1.28B | |
| GFTU.L | Grafton Group GFTU.L | GBp1,027.80 | 2.08% | 1.91B | |
| CMPR | Cimpress CMPR | $61.92 | 2.21% | 1.52B | |
| C43.F | Cosmo Pharmaceuticals C43.F | €61.50 | 6.25% | 1.06B | |
| PRTA | Prothena PRTA | $7.89 | 5.96% | 405.05M | |
| DOLE | Dole PLC DOLE | $13.84 | 0.07% | 1.31B | |
| NVTS |  Navitas Semiconductor NVTS | $7.86 | 15.76% | 2.12B | |
| GHRS | GH Research GHRS | $18.44 | 7.48% | 1.27B | |
| ADSE | ADS-TEC Energy ADSE | $9.21 | 1.43% | 692.46M | |
| AMRN | Amarin Corporation AMRN | $11.58 | 5.51% | 486.64M | |
| TRIB | Trinity Biotech TRIB | $5.90 | 8.28% | 4.79M |