Does 'Il Est Probable Que' Need the Subjunctive?

Verbs, Expressions and Conjunctions That Require the French Subjunctive

The French phrase Il est probable que / C'est probable que means "it's probable" or "it's likely," and it may require the subjunctive, depending on whether it is used affirmatively, negatively or interrogatively. When used affirmatively, it does not require the subjunctive.

Example

Il est probable / C'est probable qu'il le fait.
It's probable that he'll do it.

But when using il est probable / c'est probable que to express doubt or uncertainty, it calls for the subjunctive.

Examples

Il n'est pas probable / Ce n'est pas probable qu'il le fasse.
It's not probable that he'll do it.

Est-il probable / Est-ce probable qu'il le fasse ?
Is it probable that he'll do it?