Singapore
Best performance: Champions – 2012, 2007, 2004, 1998

Four of the 12 previous editions of the AFF Cup have been won by Singapore, who are the second most successful side in the competition’s history. The Lions are, however, aiming to make it out of the group stage for the first time since last being crowned champions, in 2012. 

More than half the squad, including captain Hariss Harun, ply their trade for the highly ambitious Lion City Sailors, while Irfan Fandi – son of the legendary Fandi Ahmad – is with Thai champions BG Pathum United. As hosts, Singapore fans will be expecting a return to the knockout rounds.

Thailand
Best performance: Champions – 2016, 2014, 2002, 2000, 1996

Five titles see Thailand stand alone as the AFF Cup’s most successful side. National icon Kiatisuk Senamuang has been involved in all of those triumphs, lifting the trophy three times as a player and then guiding the War Elephants to glory as a manager in 2014 and 2016. 

A semi-final defeat in 2018 was below par but, under Brazilian head coach Alexandre Polking, they return with star power including Chanathip Songkrasin, Theerathon Bunmathan and Teerasil Dangda, and will be targeting title number six in Singapore. 

Myanmar
Best performance: Semi-finals – 2016, 2004

Two-time semi-finalists Myanmar have appeared at every edition of the competition and, while they narrowly missed out on a place in the last four three years ago, two wins and a draw from four games was an impressive return. 

As he did in 2018, German tactician Antoine Hey leads the side into the tournament and, featuring the likes of Maung Maung Lwin and exciting young prospect Htet Htet Aung, Myanmar will be eyeing a return to the semi-finals.

Philippines
Best performance: Semi-finals – 2018, 2014, 2012, 2010

Having qualified for their first AFC Asian Cup in 2019 and reaching the semi-finals of the AFF Cup in four of the past six editions, the Philippines’ rise both on the continent and regionally over the past decade is clear to see. 

Gone are the likes of the Younghusband brothers Phil and James – talismen during the past 10 years – but inspirational captain Stephan Schröck remains while the AFC Cup’s all-time leading scorer Bienvenido Marañón is in the squad and set to make his debut having recently been naturalised.

Timor-Leste
Best performance: Group stage

This will be Timor-Leste’s third appearance in the AFF Cup having also qualified in 2004 and, more recently, in 2018 after overcoming Brunei Darussalam in a playoff to book a return to ASEAN’s premier tournament. 

While they have yet to pick up a point, the Timorese came close three years ago, losing 3-2 to the Philippines and going in front against neighbours Indonesia in a campaign that will offer hope they can create a little bit of history in 2021.

Vietnam
Best performance: Champions – 2018, 2008

A golden generation of Vietnamese talent delivered the goods three years ago when they defeated Malaysia 3-2 in the final to win the AFF Cup for the second time, a decade after they had first lifted the trophy. 

Park Hang-seo’s side, which features star quality in the likes of Nguyen Quang Hai and Nguyen Tien Linh, went on to reach the final round of the AFC Asian Qualifiers for the first time and will go into the tournament as many people’s favourites. 

Malaysia
Best performance: Champions – 2010

Tan Cheng Hoe's Harimau Malaya enjoyed a fine campaign in 2018 and claimed the notable scalp of defending champions Thailand in the semi-finals before falling just short against the Vietnamese in the showpiece event. 

Winners in 2010, when players such as Safiq Rahim and Safee Sali turned on the style, Malaysian fans will hope an exciting generation featuring Safawi Rasid and Akhyar Rasid can fire the four-time finalists to glory once more.

Indonesia
Best performance: Runners-up – 2016, 2010, 2004, 2002, 2000

No team has progressed to the final so many times without not having lifted the trophy as Indonesia, who have appeared in the main event on five occasions but have yet to taste glory after suffering a number of agonising defeats. 

Garuda legends such as Bambang Pamungkas and Firman Utina have come close to the title previously, and it’s now the turn of the likes of Evan Dimas, Egy Maulana and Asnawi Mangkualam – under Korean tacticuan Shin Tae-yong – to try and end the drought for Indonesian football.

Cambodia
Best performance: Group stage 

This will be Cambodia’s eighth appearance in the AFF Cup, having been part of the inaugural edition in 1996 and the past three campaigns. While they have yet to reach the semi-finals, a 3-1 win over Laos in 2018 marked their first victory in the competition for 16 years. 

And there is plenty of optimism around the current side, with Japan legend Keisuke Honda, the general manager, assisting head coach Ryu Hirose from afar, and Chan Vathanaka – for so long the country’s bright young hope – back to his best. 

Laos
Best performance: Group stage

Like Cambodia, Laos have never reached the knockout rounds, although just once – in 2016 – have they failed to qualify for the tournament. The current edition will be their 12th appearance.

All eyes will be on Billy Ketkeophomphone, the France-based striker who looks set to make his debut for the Laotians when they take on defending champions Vietnam on Monday.