The knockout stage was the second and final stage of the 2018 AFF Championship, following the group stage. It was played from 1 to 15 December with the top two teams from each group (two in total) advancing to the knockout stage to compete in a single-elimination tournament. Each tie was played on a home-and-away two-legged basis. The away goals rule, extra time and penalty shoot-out were used to decide the winner if necessary.
Vietnam won 3âÂÂ2 on aggregate against Malaysia in the final to win their second title.
The top two placed teams from each of the two groups advanced to the knockout stage. In Group A, Vietnam secured the group top spots with 10 points after defeating Cambodia by 3âÂÂ0 in their last match while Malaysia became the group runners-up with 9 points after beating Myanmar with similar scores of 3âÂÂ0. Meanwhile in Group B, Thailand secured the group top spots with 10 points after defeating Singapore by 3âÂÂ0 in their last match while Philippines became the group runners-up with 8 points after drawing 0âÂÂ0 against Indonesia.
The schedule of each round was as follows.
Scores after extra time are indicated by (a.e.t.), and penalty shoot-out are indicated by (pen.).
<section begin=Semi-finals />
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<section begin=Final />
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