The deal is likely to lead to the four current divisions being rearranged into a 12-12-18 set-up, with a fairer distribution of the money generated by the top clubs.
Details of the agreement have still to be sealed, but it will also lead to the two league bodies merging into one, which is likely to be called the Scottish Professional Football League.
Three meetings have already been held to discuss the proposals, with seven SPL clubs and eight from the SFL expected to attend further discussions this week.
The plans are thought to involve reconstructing the leagues in time for next season, with an agreement likely to be reached next month.
"We're agreed on a lot of things and it will be in the best interests of all of the 42 clubs," said SFL chief executive David Longmuir in a radio interview yesterday.
"We are on the right road to achieving something positive. It's important we understand the objectives of all the clubs, but we do all need each other. We needed to have a structure in Scottish football that could cover every eventuality, as we found out with the Rangers case during the summer.
"We want a structure that is a bit more dynamic than what we have just now and - a redistribution of the wealth. We'd also like more play-offs.
"It looks like being a 12-12-18 set-up. That appears to be the only way we can all agree and move forward. There is no perfect solution but we are trying. It's very important we embark on a clear programme of communication.
"It will also stand the game in good stead if we are all under one umbrella and one body. It means we can do more for the game under one roof. It has so many positives. The SPL are beginning to come round to understanding it's the best way to take the game forward."
Both league bodies are compromising on elements of their own plans. However, it is unclear what the fate of Rangers will be since broadcasters are keen for the Ibrox club to return to the top flight, but there are thought to be no firm plans to fast-track that process.