Organisers announced the decision on Wednesday night, saying they will need to talk further with “principal investors”.
The news will come as a major blow to cricket fans in Scotland.
The Euro Slam was to be the world’s first multinational T20 franchise tournament. Glasgow Giants and Edinburgh Rocks were to take part alongside four other franchises; Amsterdam Knights, Rotterdam Rhinos, Belfast Titans and Dublin Chiefs.
The first matches were due to take place in Amsterdam on 30 August, with Glasgow earmarked to play Belfast. Edinburgh’s first match was scheduled for 1 September, also against Belfast in Amsterdam.
Ten matches were to be staged at the Grange Club in Edinburgh from 6-11 September.
A number of high profile players had been signed up to take part in the tournament.
Former New Zealand captain Brendon McCullum had been due to play for Glasgow Giants but announced his retirement from cricket earlier this month.
Euro T20 Slam spokesman Prashant Mishra said: “The Board of the Euro T20 Slam, funding partners and franchise owners of this exciting new T20 tournament have reluctantly come to the decision that staging of the event will not be possible in 2019.
“We want to ensure that the inaugural staging of the Euro T20 Slam provides the best springboard to making this a truly flagship event on the global cricket calendar. As such, we believe the right course of action is to postpone the Slam to a further date. This will give us the necessary breathing space to ensure we are ready to go.
“We will work with the three cricket boards, our principal investors, the franchise owners, players and other stakeholders within the game to ensure we fulfil any commitments we have made to the extent possible. We want to ensure the goodwill and integrity that we have built up rolls on into 2020.”
Malcolm Cannon, chief executive of Cricket Scotland, said: “While this was a very difficult decision to make at this late stage, we believe that it is the right one and one which leaves us with a great opportunity to launch the Euro T20 Slam next year with its deserved noise level.
“Cricket Scotland has no regrets about trying to find innovative ways to drive cricket forward, popularise the game, and attract more investment into the sport. Indeed, the interest shown in the Slam since its launch has proved to us here in Scotland that there is a huge appetite for this type of event and for Scottish sports fans to get to see international superstars playing with and against our homegrown talent.
“We look forward greatly to working with our clubs, our fans, our players and our coaching staff to further leverage the excellent work done to date in preparation for the Slam.”