Staff at Lews Castle College are preparing to strike this week.
Lecturers in the Western Isles are paid less than colleagues in similar roles in some mainland colleges.
The EIS union say there is a £12,000 difference in pay for staff doing the same job in different colleges across Scotland.
If talks break down between the union and colleges at arbitration service, Acas, then classes will be disrupted or cancelled all day Thursday.
An official picket line is planned to form at the college gates.
EIS spokesperson, Pam Currie, maintained college chiefs are refusing to implement the agreement.
She said: “That pay deal is making sure every lecturer in Scotland gets paid the same for doing the job of teaching students and delivering SQA qualifications.”
The EIS points out police, nurses and other public sector staff get paid the same regardless of where they work.
The union highlights it is not striking for more money but to get the binding agreement
made last March implemented -
It is understood the Scottish Government position is the money set aside for the agreement has been “banked” specifically for the pay harmonisation.
Management also want lecturers to teach more classes each week.
Ms Currie said: “That might sound like a good think but we only have a finite number of days and hours in the week. So if we’re teaching more than 24 horu
A wide difference in wages exist between to Official pickets outside the gates of the college in Stornoway are being joined by supporters over the day.
Colleges pulled out of national bargaining and imposed a 1% pay rise which angers the union as it increases the size of the pay gap.
Local union official, Catriona MacAulay, said island lecturers were forced to walkout as the "last resort" in a campaign to get "equal pay in the further education sector."
She pointed out police, nurses and other public sector staff get "paid the same regardless of where they work.
"Unfortunately further education lecturers do not get paid the same. There is a disparity of over £12,000 between the lowest and highest paid in the sector."
Lecturing staff at the Lews Castle College feel very strongly about the lack of fairness, she added.
Island college lecturers prepare to strike
25 April 2017
Lews Castle College strikers last year