There were only a handful of cases of community transmission in the state after mid-April,[2] until late December 2021 when a tourist caused an outbreak that led to the cancelling of some New Year's Eve events, and the re-imposing of mask wearing rules in Perth and the Peel region.

[3] Western Australia's low case numbers were attributed to a swift introduction of restrictions by authorities, a strict state border policy, and its isolation.

[4] Western Australia confirmed its first case of COVID-19 on 21 February 2020, a man who was evacuated off the Diamond Princess cruise ship and flown to Darwin.

When he tested positive, he was flown by the Royal Flying Doctor Service to Perth, and was isolated at Sir Charles Gairdner Hospital.

[14] MV Artania departed Fremantle on 18 April following a standoff with state and federal governments over responsibility for the care of passengers and crew.

The states quickly enacted a variety of restrictions against travellers from WA who arrived since 25 January including requiring COVID testing, 5 to 14 days of self or supervised quarantine, and Victoria forbidding entry without a permit.

[30] The lockdown was lifted on 5 February, but some rules such as mandatory mask wearing, and travel restrictions, were maintained in the Peel and Perth regions.

[33] Also on 5 February, McGowan announced a A$43 million package to assist small businesses and charities in WA who suffered financially during the lockdown, in the form of a A$500 offset on their electricity bill.

Chief executive of the Australian Hotels Association WA, Bradley Woods said: "We estimate over $100 million revenue and sales has been lost as a result of this shutdown …".

Plans to increase WA's weekly international flight arrival cap were postponed to the end of February.

[36] ANZAC Day commemorations inside the lockdown area (which were anticipated to go ahead with caps on attendance) were cancelled and people were encouraged to participate in driveway dawn services, as was the case in 2020.

Under the restrictions, masks remained mandatory indoors and outdoors in the Perth and Peel regions, unless people had a medical exemption, or were doing vigorous exercise outside.

[38][39][40] In mid-June, there was controversy when the Western Australia Police accessed data from the SafeWA contact tracing app as part of a murder investigation.

[42] Due to the growing Bondi cluster in Sydney, from 11am on 23 June, Western Australia reinstated a hard border with NSW.

[44][45] She was the third person in Australia to die from an adverse reaction to an Astra-Zeneca vaccination; the first two deaths were in NSW from thrombosis with thrombocytopenia syndrome.

[48] On 28 June, a 4-day lockdown was declared, requiring people to stay home except for essential work, shopping or medical appointments.

[48] On 13 December 2021, it was announced that Western Australia would fully open its borders to COVID-19 vaccinated people from interstate and overseas on 5 February 2022,[50][51] but that re-opening was subsequently delayed.

[59] From 16 January masks were again required for indoor public areas in the Perth and Peel regions, after five new cases of SARS-CoV-2 Omicron variant.

The president of the Australian Medical Association WA, Mark Duncan-Smith, believed that the state's hospital system was not ready for the borders to be reopened.

[65] On 21 September, the Emergency Management Amendment (Temporary COVID-19 Provisions) Bill 2022 passed the lower house of the WA Parliament after a debate that finished at midnight.