| Name | Theatre or location | Principal venue | Notes / known for |
| Arena di Verona Festival | Arena di Verona | Italy: Verona | Roman arena |
| Aspen Music Festival | Wheeler Opera House | United States: Aspen, Colorado | |
| Aspendos Opera and Ballet Festival | Aspendos Arena | Turkey: Aspendos | Organised by Turkish State Opera and Ballet Directorate |
| Atlantic Music Festival Opera Workshop | Strider Theater | United States: Waterville, Maine | |
| Amazonas Opera Festival | Amazon Theatre | Brazil: Manaus | Organised by Amazonas State Government |
| Bayreuth Festival | Bayreuth Festspielhaus | Germany: Bayreuth | Richard Wagner |
| Bergen International Festival | Grieghallen | Norway: Bergen | |
| Blackwater Valley Opera Festival | Lismore Castle | Ireland: Blackwater Valley | |
| Boston Early Music Festival | | United States: Boston, Massachusetts | Early music |
| Bregenz Festival | Seebühne | Austria: Bregenz | large stage |
| Buxton Festival | Buxton Opera House | United Kingdom: Buxton | |
| Cantiere Internazionale d'Arte[1] | Teatro Comunale Poliziano | Italy: Montepulciano | Workshops of opera, music, and theatre |
| Caramoor International Music Festival | Venetian Theatre | United States: Katonah, New York | |
| Castleton Festival | Festival Theatre | United States: Castleton, Virginia | |
| Central City Opera | Central City Opera House | United States: Central City, Colorado | |
| Chautauqua Opera | Norton Memorial Hall | United States: Chautauqua, New York | |
| Cincinnati Opera Summer Festival | Cincinnati Music Hall | United States: Cincinnati, Ohio | |
| Chorégies d'Orange | Théâtre Antique d'Orange | France: Orange | Roman theatre |
| Dalhalla Opera | Dalhalla | Sweden: Rättvik | |
| Des Moines Metro Opera | Blank Performing Arts Center | United States: Indianola, Iowa | 3 mainstage productions; 2nd Stages Series: 2 productions throughout Des Moines |
| DomStufen-Festspiele | Theater Erfurt | Germany: Erfurt, Thuringia | International Opera Festival in heart of Germany, summer: one mainstage production, one production for children |
| Dorset Opera Festival | The Coade Hall | United Kingdom: Blandford Forum, Dorset | Country house opera: large-scale works |
| Drottningholm | Drottningholm Palace Theatre | Sweden: Stockholm | Early works |
| Festspiel Baden-Baden | Festspielhaus Baden-Baden | Germany: Baden-Baden | |
| Festival d'Ambronay | Abbey of Ambronay | France: Ambronay | Baroque works |
| Festival de Ópera do Theatro da Paz | Theatro da Paz | Brazil: Belém | Organized by Pará state government |
| Festival de Radio France et Montpellier | Le Corum | France: Montpellier | Rare works |
| Festival dei Due Mondi | Teatro Caio Melisso | Italy: Spoleto | |
| Festival della Valle d'Itria | Palazzo Ducale | Italy: Martina Franca | Rare works |
| Festival d'Aix-en-Provence | Théâtre de l'Archevêché,
Grand Théâtre de Provence,
Théâtre du Jeu de Paume | France: Aix-en-Provence | |
| Festival d'Opéra Baroque de Beaune | Hospices de Beaune | France: Beaune | Baroque works |
| Festival Puccini | Teatro dei Quattromila | Italy: Torre del Lago | Giacomo Puccini, Large-stage |
| Festwochen der Alten Musik | Tiroler Landestheater | Austria: Innsbruck | Early works |
| Fort Worth Opera | Bass Performance Hall | United States: Fort Worth, Texas | |
| Garsington Opera | Wormsley Park | United Kingdom: Stokenchurch, Buckinghamshire | Country house opera |
| George Enescu Festival | Romanian Athenaeum | Romania: Bucharest | |
| Glimmerglass Fstival | Alice Busch Opera Theater | United States: Cooperstown, New York | |
| Glyndebourne Festival Opera | Glyndebourne Opera House | United Kingdom: Glyndebourne | Country house opera |
| Grange Park Opera | West Horsley Place | United Kingdom: West Horsley, Surrey | Country house opera |
| Handa Opera on Sydney Harbour | Sydney Harbour | Australia: Sydney | |
| Iford Arts Festival | Iford Manor | United Kingdom: Bradford-on-Avon, Wiltshire | Country house opera |
| InterHarmony International Music Festival | Chiesa Santo Spirito, Rathaus | Germany: Sulzbach-Rosenberg | locations in 2 countries |
| Italy: Acqui Terme |
| International Punta Classic Opera Festival | Punta del Este | Uruguay: Punta del Este | Giacomo Puccini |
| Kammeroper Schloss Rheinsberg | Schlosstheater | Germany: Rheinsberg | young singers |
| Läckö Castle Opera | Läckö Castle | Sweden: Lidköping | Inner courtyard of baroque castle |
| Lismore Opera Festival | Lismore Castle | Ireland: Lismore, County Waterford | |
| Lucerne Festival | Lucerne Culture and Congress Centre | Switzerland: Lucerne | |
| Longborough Festival Opera | Banks Fee House | United Kingdom: Longborough | Country house opera |
| Maggio Musicale Fiorentino | Teatro Communale and Teatro della Pergola | Italy: Florence | |
| Miskolc Opera Festival | Grand Theatre | Hungary: Miskolc | Bartok; other operas |
| Munich Biennale | Gasteig | Germany: Munich | New opera and music-theatre |
| Munich Opera Festival | Nationaltheater München | Germany: Munich | |
| Nevill Holt Opera | Nevill Holt Hall | United Kingdom: Nevill Holt, Leicestershire | Country house opera |
| Opera Barga Festival | Teatro dei Differenti | Italy: Barga | |
| Opéra de Baugé | Les Capucins | France: Baugé | Country house opera |
| Opera Holland Park | Holland Park Theatre | United Kingdom: London | |
| Opera Memphis | Playhouse on the Square | United States: Memphis, Tennessee | |
| Opera Saratoga | Spa Little Theater | United States: Saratoga Springs, New York | Formerly known as Lake George Opera |
| Opera Theatre of Lucca | Teatro del Giglio | Italy: Lucca | |
| Opera Theatre of Saint Louis | Loretto-Hilton Theater | United States: St. Louis, Missouri | |
| OperaFest Tulchyn | Tulchyn, Ukraine | | |
| Operosa[2] | Herceg Novi, Montenegro, Bulgaria, Belgrade, Serbia | Montenegro: Herceg Novi | |
| Opernfest[3] | Kino Delphi (Berlin-Weißensee) former silent movie theatre | Germany: Berlin | |
| Pafos Aphrodite Festival Cyprus | Paphos Castle | Cyprus: Paphos | |
| Phoenicia International Festival of the Voice[4] | | United States: Phoenicia, New York | |
| Piccolo Opera Festival | Spessa Castle and various locations | Italy: Friuli-Venezia Giulia | No borders Opera experience in historical venues |
| Slovenia: Gorizia Hills |
| PromFest | Endla Theatre | Estonia: Pärnu | |
| Ravenna Festival | Teatro Communale Alighieri | Italy: Ravenna | |
| Ravinia Festival | Ravinia Park | United States: Highland Park, Illinois | |
| Rossini in Wildbad | Kurtheater | Germany: Bad Wildbad | Gioachino Rossini |
| Rossini Opera Festival | Teatro Rossini | Italy: Pesaro | Gioachino Rossini |
| Salzburg Easter Festival | Großes Festspielhaus | Austria: Salzburg | |
| Salzburg Summer Festival | Großes Festspielhaus, Felsenreitschule | Austria: Salzburg | |
| Salzburg Whitsun Festival | Großes Festspielhaus | Austria: Salzburg | |
| Mozart Week | Salzburg | Austria: Salzburg | |
| Santa Fe Opera | The Crosby Theatre | United States: Santa Fe, New Mexico | popular operas, rarely performed + North American / World premieres |
| Savonlinna Opera Festival | Olavinlinna Castle | Finland: Savonlinna | Mediaeval castle surrounded by a lake |
| Schwetzingen Festival | Schlosstheater Schwetzingen | Germany: Schwetzingen | |
| Sferisterio Opera Festival | Sferisterio di Macerata | Italy: Macerata | |
| Spoleto Festival USA | Gaillard Center, Sottile Theatre, Festival Hall | United States: Charleston, South Carolina | |
| Stars of the White Nights Festival | Mariinsky Theatre | Russia: Saint Petersburg | |
| Strasbourg Music Festival | various locations including Strasbourg Cathedral | France: Strasbourg | |
| Stålboga Summer Opera | Music pavilion at Stålboga manor house | Sweden: Södermanland | Country house opera |
| Tanglewood Music Festival | Tanglewood Music Center | United States: Lenox, Massachusetts | |
| Teatro dell'Opera di Roma | Baths of Caracalla | Italy: Rome | Summer Festival |
| Utah Festival Opera & Musical Theatre[5] | Ellen Eccles Theatre and Utah Theatre | United States: Logan, Utah | Performs 5-6 works of Opera and Musical Theatre in two venues. |
| Verbier Festival and Academy | Salle Médran | Switzerland: Verbier | |
| Waterperry Opera Festival | Waterperry Gardens | United Kingdom: Oxfordshire | Country house opera |
| Wexford Festival Opera | Wexford Opera House | Ireland: Wexford | Rare works |
| Vicenza Opera Festival[6] | Teatro Olimpico | Italy: Vicenza | Roman theatre, Ivan Fischer Opera Company |
| Wiener Festwochen | Theater an der Wien | Austria: Vienna | Contemporary works |
| Wolf Trap Opera Company | Filene Center | United States: Vienna, Virginia | |
