Labour has hit its equal lowest level in the polls since Jeremy Corbyn became party leader.
The latest YouGov poll for The Times put Labour at 24%, matching a survey for the company in December last year.
It showed the party's worst performance since Gordon Brown was Prime Minister in 2009, during one of the last Government's most unpopular periods.
Meanwhile, the Tories enjoyed a 16-point lead on 40%, with Ukip just 10 points behind Mr Corbyn's party on 14%. The Liberal Democrats remained at 11%.
In a potentially worrying development for Labour, Ukip performed better with working class voters in the latest polling, acquiring 23% support among these voters compared to Labour's 20%.
Labour is facing a threat from Ukip in the upcoming Stoke-on-Trent Central by-election, where Ukip leader Paul Nuttall will contest the seat vacated by former shadow education secretary Tristram Hunt.
The YouGov survey was carried out on February 5 to 6, before Mr Corbyn successfully ambushed Theresa May at Prime Minister's Questions with leaked text messages about a so-called "sweetheart deal" with Surrey County Council over funding for social care.
The poll came as Labour's deputy leader Tom Watson said Mr Corbyn needed to turn round his popularity ratings, telling the BBC's Andrew Marr Show on Sunday: "He has to explain those and he has to improve on them and he's well aware of that."
:: The YouGov poll for The Times asked 1,704 adults about their voting intentions between February 5 and 6.