The 2020 AFL season was the 124th season of the Australian Football League (AFL), the highest level senior men's Australian rules football competition in Australia, which was known as the Victorian Football League until 1989. The season featured eighteen clubs.

Played during the first year of the COVID-19 pandemic, the season commenced on 19 March and was suspended four days later; it resumed on 11 June and ran until 24 October. A shortened season was played, comprising a 17-game home-and-away season followed by a finals series featuring the top eight clubs; all matches were shortened to 80% of their usual length. Virus outbreaks and interstate travel restrictions precluded games in many states for much of the season, with all clubs spending parts of the season temporarily relocated to quarantine hubs, particularly in South East Queensland where almost half of all matches were played – including the Grand Final, the first time it had been played outside Victoria. Health directives resulted in restricted match attendances throughout the year, including thirty matches played behind closed doors.

The premiership was won by the Richmond Football Club for the 13th time and second time consecutively, after it defeated by 31 points in the 2020 AFL Grand Final.

Impact of the COVID-19 pandemic

The 2020 season was disrupted by the COVID-19 pandemic, which was formally declared a pandemic by the World Health Organization on 11 March 2020, eight days prior to the scheduled start of the premiership season. Restrictions imposed by the different state governments related to social distancing, lockdowns of non-essential services which lasted for three months across the country, and border controls for interstate and international travel, all had significant effects on the completion of the 2020 season.

Fixture Prior to the commencement of the season, anticipating that the season would be forced to cease at the peak of the virus, the AFL shortened the fixture from 22 matches per team to 17, with each team playing each other once and serving one bye. The season then commenced on 19 March as originally scheduled; but as restrictions, followed by periods of formal quarantine, were introduced on interstate travel, the season was suspended after Round 1.

The season was suspended for more than two months. On 15 May, as most states began easing restrictions, the league's plan to resume the season was announced: clubs began non-contact training from 18 May, and full contact training from 25 May ahead of resuming competitive matches from 11 June, with the revised fixture released gradually throughout the year, and changing regularly and often at short notice when the situation forced it.

The first major fixturing challenge occurred in the aftermath of Round 4, when a spike in Victorian COVID-19 cases prompted other states to either impose tighter quarantine restrictions on Victorians, or defer the relaxation of restrictions already in place. Although this forced two planned Round 5 matches— vs and vs —to be redrawn at less than a week's notice (Richmond instead faced Melbourne in Victoria, and Sydney faced West Coast in Queensland) and the entire planned Round 6 and 7 fixtures to be redrawn, the season continued without suspension. The gradual release of the fixture also allowed the flexibility to reschedule any games which were postponed due to positive COVID-19 tests among players or staff.

When games were postponed or rescheduled at short notice, other games within the same round were often also rescheduled to ensure the primetime television slots were filled.

Club medical restrictions During the peak of the hiatus, players were allowed to train only within the strict limits of the government restrictions on public gatherings; at the height of the pandemic in April and May, when gatherings larger than two were restricted, players could train only in pairs. When the league returned to training and playing, it was done with strict, enforceable protocols and monitoring in place to ensure that the clubs would not suffer a virus outbreak, and that any virus cases could be contained with minimal impact to the wider competition. To this effect, players, umpires and staff were regularly tested for the virus and continued to train mostly in small groups, allowing individual players or small groups to be segregated and contained in the event of positive cases. Players and club personnel were subject to protocols which extended to players' personal lives, which were above and beyond the lockdown guidelines still in place for the general public, in order to protect the AFL season from suffering an outbreak; and families and partners who were part of quarantine hubs came under the same restrictions.

There were many breaches during the season, resulting in fines for the players and clubs involved, or suspensions in the most egregious cases: 's Sydney Stack and Callum Coleman-Jones (ten matches each), for being involved in a fight outside a Surfers Paradise kebab shop in the early hours of 4 September. 's Elijah Taylor (rest of season, which amounted to six home-and-away matches), for bringing his girlfriend into the club's Perth quarantine hotel. assistant coach Ben Hart (six training weeks), for allowing training groups to be too close to each other on a quarantine camp in early May. 's Steele Sidebottom (four matches) and Lynden Dunn (one match), for travelling in an Uber and visiting more than one unauthorised house, the night concluding with Sidebottom being driven home by police. 's Peter Ladhams (three matches) and Dan Houston (two matches), for inviting non-authorised residents to their house. 's Charlie Spargo (two matches) and Kysaiah Pickett (one match), for travelling via an Uber to an unauthorised house for a gathering. 's Ollie Wines (one week), for inviting a non-authorised resident to his house. 's Brandon Zerk-Thatcher (one week), for breaching living arrangement protocols.

Throughout the season, AFL-listed players were not permitted to participate in the state league competitions (the VFL, SANFL, WAFL and NEAFL) due to the greater risk of external threats in the semi-professional state league environment; this meant there was no formal competitive reserves football for players who were not selected in the seniors. (The NEAFL and VFL ended up cancelling their seasons altogether). Clubs based in the same state were permitted to arrange ad hoc scratch matches for their unselected players against each other and in empty stadiums to enable some match practice; these could be stand-alone games or curtain raisers to senior games.

Through all of these restrictions, there were ultimately no confirmed positive cases of the virus among the league's players. The only positive tests ever returned were by Conor McKenna (), who returned two false positives, followed by a confirmed negative, over the round 3 weekend, resulting in the cancellation of Essendon's scheduled match against . Coming during a phase of the pandemic when any positive test was taboo in society, McKenna received negative media scrutiny and social media abuse after the positive results.

Quarantine hubs and club relocation

Interstate travel restrictions and quarantine periods were a significant impediment to the completion of the season after the resumption, with many state border crossings subject to mandatory 14-day quarantine periods. Western Australia and Tasmania had the tightest restrictions, requiring quarantine for all entries throughout the entire season; South Australia had similar restrictions which were loosened after Round 5. Border crossings around the rest of the country were freer; but, as second waves of virus cases occurred in Victoria (after Round 5) and New South Wales (after Round 10), quarantines were imposed on travellers leaving those states. This precluded a conventional interstate home-and-away fixture, and meant that Queensland – which maintained few virus cases and had the most favourable quarantine arrangements – became critical to the completion of the season.

The border restrictions were managed by requiring several clubs to relocate outside their states; or, to set-up in weeks-long quarantine hubs, in which clubs travelled at the same time to a restricted state for an extended three- or four-week trip, quarantined there and played several games against other teams in the hub. Players' immediate families were permitted to join them at the league's expense, but were subject to the same lifestyle restrictions and virus testing regime as the players.

The relocation of all ten Victorian clubs occurred after Round 5. , , , , and moved to south-east Queensland; and , , and moved to New South Wales. The relocation of the six New South Wales based clubs (, and the four Victorian clubs) to Queensland then occurred after Round 8. These relocations lasted until the end of the season.

The season's first quarantine hub occurred immediately after the resumption, and featured the clubs from South Australia and Western Australia – the most tightly restricted state at that time. The clubs were relocated to south-east Queensland – with the Western Australian teams arriving in Round 2 and the South Australian teams arriving in Round 3 (after their Round 2 Showdown game in Adelaide). The visiting teams played each other and the two Queensland-based clubs in a hub until Round 5. The two West Australian teams remained in the hub for an additional week and flew back to West Australia following Round 6, and the South Australian hub members returned to South Australia after Round 5 but still travelled weekly to Queensland over subsequent weeks.

From that point on, three three-week quarantine hubs were staged in Perth, to allow matches to be played there despite season-long quarantine requirements. Each time, two interstate clubs travelled at once from Queensland, and played each other while in quarantine, then the two Perth clubs while out of quarantine. These hubs were: Rounds 7–9: and Rounds 9–12: and (including a bye) Rounds 12–14: and

and later returned to a Queensland hub for the final four rounds of the home-and-away season.

Teams could also travel from Queensland to the Northern Territory, where three games were played. However, season-long Tasmanian border restrictions to all states resulted in no AFL matches being played in the state for the first time since 2000.

Border restrictions ultimately also precluded the playing of any finals in Victoria or New South Wales – including the Grand Final – and limited finals in Western Australia to the first week only, since the bye week after Round 18 allowed time to quarantine. For the first three weeks of finals, clubs unable to play in their home states were given the option to nominate a preferred home ground from the Gabba, Metricon Stadium and Adelaide Oval for home finals. On 2 September, the Grand Final was formally scheduled for Saturday 24 October, the latest in the year a Grand Final had been played; it was scheduled at night to avoid a clash with the 100th running of the Cox Plate that afternoon, making it the first Grand Final not to be played in the afternoon timeslot; and, it was scheduled at the Gabba, making it the first AFL Grand Final to be played outside of Melbourne.