They are the first names to be announced for the event in February at the O2 Arena in London and broadcast on ITV.
Swift last played at the Brits in 2013, performing her hit I Knew You Were Trouble.
No word on what she'll sing this time but it's likely to be a hit from her latest number one album 1989.
Ed Sheeran was among the artists to take to the stage at last week's BBC Music Awards, collecting the British artist of the year prize and he is tipped for further glory at the ceremony on 25 February.
But at next year's Brits will it just be him and his guitar? Or can we expect a collaboration with someone unexpected?
Sam Smith started the year topping BBC's Sound of 2014 in January.
He then went onto win the Brits Critics' Choice award, and has just been nominated for six Grammy's including best new artist.
His single Stay With Me is also up for best pop performance and record of the year.
Further names for the event - officially called the Brit Awards 2015 - will be announced over the coming weeks.
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Taylor Swift, Ed Sheeran and Sam Smith have all been booked to appear at next year's Brit Awards ceremony.