What is this effect on his vocals?
 

Start at 0:25. Song called Icarus by Cory Henry (sry can’t add a link since I am a new user)
Thank you in advance.

I’d say that first of all it’s double-tracked (somewhere between two and four layers), with him singing different harmony parts, and the different layers are slightly delayed towards each other (up to 50ms), in order to find that „Sweet spot”

And because it’s multiple vocals layered on top of each other and delayed, they create this sort of chorus/flanger effect.

I could be wrong though

Ok. Thanks for the reply.

Looper
 

I'm pretty sure he's got a looper set to dub. You'll set down a rhythm ground track, then dub melody, counter-harmony, and counter-melody in that order.