To erase a Snapchat conversation, open Snapchat, tap your profile icon → gear icon (Settings) → scroll to Clear Conversations under the Account Actions section. Select the conversation you want to erase and confirm. This removes it from your chat list but doesn’t delete it from the other person’s account.
To erase a Snapchat conversation, open the Chat screen, press and hold the friend’s name, then tap “Chat Settings” → “Clear from Chat Feed.” This removes it from your chat list, but saved or unopened messages may still be visible.