Euronext Lisbon (EURONEXTLIS), formerly known as Bolsa de Valores de Lisboa e Porto, is the main stock exchange in Portugal. It was founded in 1769 under the name “Assembleia dos Homens de Negócio” and is headquartered in Lisbon, the country's capital and largest city. The exchange was merged into the pan-European exchange Euronext in 2002, which is currently the largest exchange in continental Europe. EURONEXTLIS is supervised by the Portuguese Securities Market Commission (CMVM) and is subject to both E.U. and Portuguese regulations. All transactions are processed through a trading system called the Universal Trading Platform (UTP), which will be replaced by a new multi-market platform called Optiq. It lists 53 companies with a total market cap of €66 billion and also houses bonds and ETFs.

Among the listings are well-known and actively traded companies such as Banco Comercial Português, Galp, The Navigator Company, Mota-Engil and EDP. The main stock index is the PSI-20, a free float market capitalization weighted index which tracks the performance of the 20 largest listed companies. It is widely recognized as the benchmark index for the Portuguese stock market. Related indices are the broad PSI All-share index and the PSI 20 GR, a gross total return index that tracks the capital gains of the PSI 20 companies over time. All constituents are screened for eligibility and reviewed annually but there is room for quarterly fast entries or replacements. EURONEXTLIS operates several indices that reflect the performance of national sectors and industries. Portuguese stocks are also included in various European indices such as the Euronext 100 index, which tracks the performance of the largest and most liquid European stocks.