The sixth and last seat was a close contest between third Liberal candidate Linda Reynolds and second Labor candidate Louise Pratt. Reynolds was ahead in the ABC's detailed count projection, with Antony Green predicting on 10 April "It is clear the Liberals will win the last seat". The result was confirmed by the Electoral Commission on 29 April. The score at the final count was 188,169 to Reynolds versus 176,042 for Pratt, a margin of 12,127. The projected margin on Green's calculator, which treated all votes as above-the-line, was a narrower 8,109.
Candidates
There were a number of candidate changes from the original election. Notable changes included:
Shane Hill replaced Peter Foster as third candidate on the Labor ticket
Fiona Patten, who was the lead Sex Party candidate in Victoria in 2013, became their lead candidate at the special election
The Socialist Equality Party and Australian Independents contested the 2013 election in Western Australia, but did not contest the special election. The Socialist Alliance, Pirate Party, Voluntary Euthanasia Party, Building Australia Party, Mutual Party, Republican Party and Democratic Labor Party did not contest the 2013 election in WA, but decided to contest the special election. Sitting members are shown in bold text. Tickets that elected at least one member in 2014 are highlighted in the relevant colour and successful candidates are indicated with an asterisk. Candidates marked with ‡ were declared elected after the final count in 2013.
17 October – A recount of all "above-the-line" Senate votes made in Western Australia is initiated after an appeal by the WA Greens and the Australian Sports Party is upheld.
31 October 2013 – The AEC announces that it is unable to find 1,375 ballot papers during the WA Senate recount.
4 November 2013 – The AEC declares the result of the WA Senate recount, awarding the last two seats to the Greens and Australian Sports Party, instead of the ALP and Palmer United Party.
15 November 2013 – The AEC, Palmer United candidate Wang, and voter Simon Mead lodge a petition with the High Court of Australia in its capacity as the Court of Disputed Returns, asking that the WA Senate result be declared null and void.
20 February 2014 – The Court of Disputed Returns voids the results of the WA Senate election. Hayne ruled that the margins between Palmer United and the Australian Sports Party for the fifth seat and the Greens and ALP for the sixth seat were far exceeded by the number of missing ballots. Hayne ruled that since the voters who cast those missing ballots had effectively been "prevented from voting", no remedy short of a new election was appropriate.
21 February 2014 – Electoral Commissioner Ed Killesteyn announces his resignation, which will take effect on 4 July 2014.
28 February 2014 – McCusker announced the election date as Saturday 5 April 2014
13 March 2014 – closing date for nomination of candidates.
The Senate after the 2013 election, once the new senators' terms started on 1 July 2014, was originally going to consist of the Coalition government on 33 seats with the Labor opposition on 25 seats and a record crossbench of 18 – the Greens on ten seats, Palmer United on two seats, with other minor parties and independents on six seats – the LDP's David Leyonhjelm, Family First's Bob Day, Motoring's Ricky Muir, Sports Party's Wayne Dropulich and incumbents Nick Xenophon and the DLP's John Madigan. The Coalition government would originally have required the support of at least six non-coalition Senators to pass legislation. Most Senate votes cast in Western Australia were subject to a formal recount. During the recount it was determined that WA Senate ballot papers could not be located. After the final recount the result was duly declared which changed the last two predicted WA Senate spots from Palmer and Labor back to Sports Party and Greens. Mick Keelty, a former AFP Commissioner, was requested by the AEC to investigate the issue of the misplaced ballot papers. On 15 November, the AEC petitioned the High Court, acting as the Court of Disputed Returns, to seek an order from the court that the WA Senate election of all six senators be declared void. A record number of candidates stood at the election. Group voting tickets came under scrutiny because multiple candidates were provisionally elected with the vast majority of their 14.3 percent quotas coming from the preferences of other parties across the political spectrum. "Preference whisperer" Glenn Druery organised tight cross-preferencing between many minor parties. The Sports Party's Wayne Dropulich won a Senate seat on a record-low primary vote of 0.2 percent in Western Australia, his party placing coming 21st out of 28 groups on primary votes. The result caused discussion across a range of organisations and parties about whether there should be changes to the GVT system.