The winner of the contest between Anas Sarwar and Richard Leonard will be announced in around ten weeks’ time on 18 November.
In the meantime, those not already eligible to vote have until 9 October to become registered supporters for a £12 fee.
The arrangements for the election, including the size of the fee, were determined at a meeting of Scottish Labour’s Executive Committee in Stirling yesterday.
The registered supporter fee is substantially more than the £3 fee introduced by Ed Miliband and which led to the suggestions that the process to elect Jeremy Corbyn in 2015 had been infiltrated by saboteurs.
It is, however, less than the £25 fee required last year when Jeremy Corbyn saw off a challenge from Owen Smith.
The election will be conducted on a one member, one vote basis, with party members, registered supporters and members of affiliated trades unions, who have paid the political levy eligible to take part.
Full membership of the party is £4 a month or £2 a month for those without a wage.
Nominations will close on 17 September and the contest will then run for two months, with the vote on 17 November.
Eight regional hustings will be held, as well as a women’s and a young Persons’ hustings. Sarwar, who is seen as the Labour moderates choice, and Leonard, a former GMB organiser who is expected to secure the support of the left-wingers and trade unionists, put their names forward following the unexpected resignation of Kezia Dugdale.
Dugdale’s departure meant she became the third Scottish Labour leader to quit since the 2014 referendum. Sarwar said: “Our campaign is now under way and I look forward to speaking to thousands of members, supporters and trade unionists.
“I will also address the hundreds of thousands of Scots who may not be Labour members, yet share our values and vision for a fairer Scotland.”
Leonard said: “We need to use this as an exercise in building up the party and the wider Labour movement and sowing the seeds of both unity and unity of purpose: setting out a vision of a more equal Scotland with full employment in a sustainable economy funding quality public services, providing dignity for our pensioners and hope for our young people.”