The additional services bring the number of routes flown by the airline from Bristol to eight, alongside Aberdeen, Hamburg, Munich, Frankfurt and Milan.
Paris and Düsseldorf flights start on April 27, with the Nantes summer-only service running between July 4 and September 12.
Fares to the French capital start at £69 one way, with Düsseldorf and Nantes £79.
Paris flights will run six days a week with two flights a day Monday to Friday, and one flight on Sunday.
Bristol-Düsseldorf will operate six times a week, Sunday to Friday, with Nantes served Tuesdays and Saturdays.
The new destinations will be operated by a 49-seat Embraer 145, with a Tuesday flight to Nantes operated by a 37-seat Embraer 135.
Bristol airport chief executive, Robert Sinclair, said: “Direct flights to European cities such as Paris, Düsseldorf and Nantes provide passengers with a convenient local alternative to the London airports, saving them time and money in the process.
“The double-daily weekday service to the French capital’s major airport, Paris Charles de Gaulle, adds capacity to another major global hub and makes a same day return possible for business passengers.”
BMI Regional chief executive, Cathal O’Connell, said: “Bristol is already a substantial hub for the airline, allowing us to service some of Europe’s most exciting business and leisure destinations.
“Flying twice a day to Paris means that business travellers can now have a full day of business in the French capital, rather than having to overnight.
“Düsseldorf is the centre of the Rhine-Ruhr and an international business and financial centre, renowned for its fashion and trade fairs, and BMI Regional the only airline to connect businesses in the south-west directly to the capital of North Rhine-Westphalia.
“Nantes is the gateway to the Loire region, and the perfect place for a weekend break, or a holiday among the world famous vineyards and chateaux.”
Sourced from Travel Weekly