EastEnders drew its lowest audience share in more than five years on Tuesday, with an average of 6.8 million viewers tuning in.
Tuesday's EastEnders featured ex-Bill actor Billy Murray (centre)
The BBC One soap attracted 28% of the available TV audience, its lowest share since November 1999.
It was beaten by ITV1's Emmerdale, as an average of 9.8 million watched character Charity Dingle wed Tom King.
An EastEnders spokesman said: "It's a shame that competitive scheduling means that soap fans lost out last night."
The Emmerdale double bill on Tuesday drew a 41% audience share, with actress Patsy Kensit's character Sadie King playing a central role.
It was the third time Emmerdale has beaten EastEnders in a head-to-head ratings battle.
An Emmerdale spokeswoman said: "Sadie and Charity's storyline has really grabbed the audience's imagination and we are thrilled to have beaten EastEnders
yet again, starting the year as we intend to go on."
Tuesday's episode of EastEnders introduced new members of the series' Moon family and a new gangster in the form of ex-Bill star Billy Murray.
The drop in audience share came after EastEnders was named the most watched soap on Christmas Day, when it attracted 12.3 million viewers.