When Does "Ted Lasso" Season One (2020) Take Place?
"Ted Lasso" season one is a comedy television series showrun by Bill Lawrence that premiered August 14th, 2020. So when is "Ted Lasso" season 1 set?
It takes place in the years:
We know this because in season one episode one "Pilot" on the wall of photographs Rebecca Welton refers to as ..."a wall of our previous owners." one photograph has a plaque below it that reads "RUPERT MANNION Since 1987" so it must be during or after 1987 AD.

2019 AD - 2020 AD
We know this because in season one episode one "Pilot" on the wall of photographs Rebecca Welton refers to as ..."a wall of our previous owners." one photograph has a plaque below it that reads "RUPERT MANNION Since 1987" so it must be during or after 1987 AD.
More specifically, during season one episode ten "The Hope That Kills You", Coach Theodore "Ted" Lasso says, "This town got a weird way with words, don't it? I mean, c'mon y'all, it's 2020, let's just call them cigarettes, alright?" so it is almost certainly 2020 AD at the end of the season's story. In the real world, the British football/soccer Premier League seasons usually run from August to May of the next calendar year. Since it's 2020 AD at the end, it must be 2019 AD at the start of the show.
Specifically, the 2019 to 2020 season started on August 9th, 2019 AD and ended on July 26th, 2020 AD in the real world. So it’s very likely that it’s August of 2019 AD during season one episode one "Pilot" and it’s July of 2020 AD during season one episode ten "The Hope That Kills You", the season finale.
A complete lack of mentions of the famous and tragic 2020 worldwide COVID-19 pandemic suggests it can't possibly be 2020 AD but the dates are fairly clear. Though the 2020 season was cancelled in the real world due to the pandemic presumably the covid-19 pandemic did not happen during 2020 AD in the fictional world (diegesis) of "Ted Lasso".

