Repost to feed keeps the post on your profile, in the Reposts tab, and puts it in your followers’ feeds. Add to your status puts it in your story, where it disappears after 24 hours. Both start from the repost button under the post.

Your status and your story are the same thing. The repost sheet calls it status, and the rest of the app calls it story.

Side by side

Repost to feedAdd to your status
How long it lastsIt stays. The app calls it permanent24 hours
Where it showsYour profile’s Reposts tab, and the feeds of people who follow youYour story
Who sees itWho you pick: Everyone, Followers or Only meWhoever can see your stories: everyone if your account is public, your followers if it’s private
Your wordsUp to 280 charactersUp to 200 characters
Which postsOnly posts shared with EveryoneAny post that isn’t for a circle or Only me
The person who postedGets a notificationIsn’t told

Which one to pick

Pick Repost to feed for a post you want to keep on your profile, so people who visit it later can find it. Pick Add to your status to pass something on for a day, the way you’d share a story.