Call the Midwife started in 2012 and follows a group of East London midwives who deal with racism, domestic violence and mental health problems in the 1950s and 1960s.
The announcement of seasons 14 and 15 means the series will run until 2026.
Creator Heidi Thomas said she was "overjoyed" at the renewal which will see the drama move into the 1970s. She added the new series will explore the lives of the midwives and nuns in their personal and professional lives at the convent they work at - Nonnatus House. Thomas said: "We are a family behind the scenes, on the screen, and in front of the telly, and I'm thrilled that we're all heading into the 1970s together."
The thirteenth season was previously confirmed by the BBC and filming will begin in the spring. Meanwhile, the twelfth season of the BBC One series returned on January 1 this year following the 2022 Christmas special which averaged 4.5 million viewers in the overnight ratings. It was the fourth most watched Christmas Day celebration program after the King's Speech, the Strictly Come Dancing Christmas special and Michael McIntyre's Christmas Wheel.
Seasons fourteen and fifteen will feature eight 60-minute episodes each, along with Christmas specials.
Over the years, the series has featured several actors, including Miranda Hart, Helen George, and Jenny Agutter. When the series began, it was loosely based on the bestsellers of former nurse and midwife Jennifer Worth. She died in 2011 - the year before the first season aired.
Dame Pippa Harris, executive producer, said the longevity of the series is an "amazing achievement and it's a testament to the passion and dedication of our cast and crew, of whom I'm very proud".
The final episode of the current series airs on Sunday 26 February at 8pm on BBC One and BBC iPlayer.