The economy shrank between July and September. A recession is defined as when the economy contracts for two consecutive three-month periods.
However, in December alone the economy dropped by 0.5% partly due to strikes across health, trains and Royal Mail.
The Bank of England still expects the UK to enter recession this year.
But it will be shorter and less severe than previously thought.
Darren Morgan, director of economic statistics at the Office for National Statistics, said: "In December public services were hit by fewer operations and GP visits, partly due to the impact of strikes, as well as notably lower school attendance.
"Meanwhile, the break in Premier League football for the World Cup and postal strikes also caused a slowdown."