D&D 5E Suffocating

[mrpopstar]

Yes, that's true. It's all about context. If one PC gets grabbed by an otyugh and dragged underwater, then a saving throw to hold onto their breath seems appropriate. If another PC then decided to jump in to rescue the first PC, then an ability check be appropriate, should the DM decide that there's a chance that the second PC might not be able to get a good enough lungful of air first, for whatever reason.

Yep! An ability check is something a character actively attempts to accomplish, whereas a saving throw is a split-second response to the activity of someone or something else.

Personally, I wouldn't call for an ability check unless the second character takes damage while holding their breath.