John Cordner (3 July 1816 – 22 June 1894) was the first Unitarian minister in Canada.
Cordner studied at the Royal Belfast Academical Institution, then worked in commerce.
That year, he emigrated to Montreal to become minister to the first Unitarian congregation in Canada.
Cordner's ministry was successful and popular, especially among the upper-middle classes and the business elite.
In sermons and speeches, he championed progressive issues: world peace, woman's rights, and anti-slavery in the US, among others.