Simbine started his 2020 season with a 150 metre race at the University of Johannesburg Stadium on 14 February, equalling the South African record time (15.08) while jogging to the finish line, but with no wind information.

[14][15] He would not be able to compete until leaving South Africa in mid-August for Europe, winning a series of 100 m competitions in Marseille, Rovereto, and Bellinzona in times of 10.19, 10.17, and 10.02 seconds respectively.

He finished his season in September with a 100 m victory at the Rome Diamond League, trailing Arthur Cissé of the Ivory Coast for the first 85 m before passing to win in 9.96 seconds.

[15] Simbine started the season with a 10.00 seconds win in the 100 metres at the Athletix Invitational in Johannesburg on 23 March, which would have been a leading time but for the wind velocity, which was just over the allowable +2.0 m/s limit.

[20] On 6 July, racing at the Hungarian Athletics Grand Prix, Simbine set a new national and African record of 9.84 seconds in winning the final.

[22] On 9 August, Simbine finally won an Olympic medal as part of the South African 4 × 100 metres relay team by claiming silver.