Hearts have been consigned to a shortened season in the Scottish Championship after the final attempt at league reconstruction failed.
Only 16 of the 42 clubs backed plans for a 14-10-10-10 set-up following an informal vote.
The Scottish Professional Football League board has now "agreed to draw a line under reconstruction talks".
It was also confirmed that Championship clubs had approved a reduced 27-game campaign, which is scheduled to kick off in October.
The vote means Hearts, Partick Thistle and Stranraer have all had their relegation ratified - unless the Edinburgh club follow up with their threat of legal action and manage to get their fate reversed.
It means Northern Ireland internationals Liam Boyce, Michael Smith and Bobby Burns all face a season in the second tier, with star striker Boyce already having confirmed his intention to remain at the club he joined in January.
SPFL chief executive Neil Doncaster said: "In recent weeks, we've been consulting closely with our clubs regarding possible reconstruction and, based on the feedback we received, the board decided to ask all 42 clubs to give their views so that we could have absolute clarity, which we've achieved today.
"Whilst a number of clubs were in favour of a new divisional set-up, the support for it was insufficient and we will now move forward with a fixture programme for season 2020-21 based on the current 12-10-10-10 structure.
"Due to the restrictions forced upon us by the coronavirus outbreak, the Championship clubs also voted overwhelmingly to play each other three times next season, rather than four, which enables a later start to the Championship league season.
"Now that we have a confirmed structure for next season, the SPFL's fixturing team will begin work on the Premiership fixture list, which will start on the weekend of 1 August, and the Championship fixture list, which will start on the weekend of 17 October."