The suspended 2019/20 season (due to Coronavirus outbreak) was to be Thornton Hibs' last as part of the Junior Association following a successful application to join the East of Scotland Football League.

The Hibs' first game as a senior club came on Saturday 10th October 2020 in the EoSFL First Division Conference A against Edinburgh South. Daniel McNab made the history books when he struck the opener (in a 3-0 win) from the penalty spot. Also of note from this game is that Edinburgh South became the 100th different opponent that Thornton Hibs had faced in the League since joining the Junior ranks in 1935.

The first foray into cup competition was against Rutherglen Glencairn in the South Region Challenge Cup. Played at the neutral venue of Bayview Stadium (home of East Fife) on Saturday 21st November, an early strike from Garry Thomson jnr was enough for the Hibs to progress.

A little piece of history was made in a league match at Craigroyston in November 2020 when cousins Garry Thomson snr and Garry Thomson jnr both scored a hat-trick in the 6-2 win.

The Hibs reached their first final as a senior club when they played Luncarty at Moorside Park in the Alex Jack Cup in November 2022. Despite goals from Jamie McNeish and Garry Thomson, they lost out 2-3 in front of around 450 spectators.