Lone ACT MP John Banks is the party's new leader.
ACT made the announcement on Thursday afternoon to say Mr Banks will take over at the helm of the party which has been without a leader since Don Brash stepped down on election night in November.
Dr Brash served as leader for only seven months, after rolling Rodney Hide from the top spot last April.
ACT received only 1.07 per cent of the party vote in the election, but as Mr Banks won the seat of Epsom, he returned to parliament as its sole MP.
Mr Banks is also a former National MP, having been in parliament from 1981 to 1999, and was mayor of Auckland City from 2001 to 2004, and from 2007 to 2010.
NZN