"The LNG terminal is one of the major issues facing Estonia in ensuring security of energy supply, as is the creation of proper competition in the gas market," Taavi Veskimagi, head of grid company Elering, said in a statement.
The companies said they were seeking EU funding for the project.
The plan could provide competition to an LNG terminal which southern neighbour Latvia says it should host and which also needs EU funds.
Russia is the sole natural gas supplier to all three Baltic states. The dominant shareholders in the domestic gas companies are Gazprom and Germany's E.ON.
The Estonian government is considering how to separate the gas distribution network from gas supply to meet European Commission competition directives.