Smith, 20, joined the programme when she was just six years old, but has now decided it is time to move on from her role as Tiffany Butcher-Baker and try new things.
A video tweeted by EastEnders on Friday showed Smith's colleagues giving her leaving presents and making a speech as she stood tearfully in her Walford kitchen after filming her final scene.
The tweet was captioned: "Today was a sad day on the set of #EastEnders as we said goodbye to the amazing @maisie_smith_, who finished filming her final scene as the iconic Tiffany Butcher-Baker. But we couldn’t let her go without a small surprise and a proper Walford farewell – take a look here."
Today was a sad day on the set of #EastEnders as we said goodbye to the amazing @maisie_smith_, who finished filming her final scene as the iconic Tiffany Butcher-Baker. But we couldn’t let her go without a small surprise and a proper Walford farewell – take a look here. pic.twitter.com/D0i1hyFVeO
— BBC EastEnders (@bbceastenders) October 8, 2021
Smith said: “It’s time to say farewell to Tiff! I’ve grown up on EastEnders since 2008, and have learnt from the best over the past 13 years.
“I’m very excited for my next challenge and thank the BBC for the opportunity they gave me as a six-year-old.”
Talking about the news, EastEnders executive producer Jon Sen said: “We are all very sad to see Maisie leave.
“She’s been a wonderful company member during her time at EastEnders and it’s been a privilege to see her blossom into the star she is.
“She has created an iconic character in Tiff and the door is always open to her return. We wish her all the very best for her future projects.”
Tiffany's key storylines in Albert Square have included a shocking grooming plot and becoming a drug dealer.
Smith's final scenes in the role are due to air this December, although her exit storyline has not yet been confirmed.
Last year, Smith was a contestant on Strictly Come Dancing where she impressed with her skilled routines alongside Gorka Marquez.
The pair made it to the final and finished as runners-up to Bill Bailey and Oti Mabuse.
Smith is said to have been offered a number of other work opportunities since starring in Strictly, but is thought to have been unable to take them up while she is still contracted at the BBC soap.
Her EastEnders character Tiffany is the daughter of soap favourites Ricky Butcher (Sid Owen) and Bianca Jackson (Patsy Palmer), and was named after Bianca's late best friend Tiffany Mitchell (Martine McCutcheon).
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