The 1884 East Coast by-election was a by-election held on 16 June 1884 in the electorate during the 8th New Zealand Parliament.
The by-election was caused by the resignation of the incumbent MP Allan McDonald.
He was replaced by Samuel Locke. A show of hands had preferred Rees, who said he was opposed by the government.
Rees subsequently accused Locke of "corrupt practices" during the by-election. Michael Gannon decided to stand for the in the (general election) held on 22 July, and came second.
The following table gives the election result: