Hi Eric, I'm having trouble following your instruction. Studying the "Manage and delete" link you sent, the only section that seems relevant is how to "Turn Contacts on or off for an account," which says: "To remove contacts, turn off Contacts, then tap Delete from My iPhone." This appears to be invalid. I am looking at Settings>Accounts. To simplify my iphone, I deleted a Google account, and I un-checked "contacts" for accounts Yahoo and Outlook, leaving contacts checked ON for only my iCloud account. This did NOT remove non-iCloud contacts from my phone.
Apple's instruction adds: "Delete from My iPhone." I see "Delete Account" at the bottom of the yahoo and outlook accounts, but that would delete the account, not just contacts right? I still want calendar and email for my yahoo and outlook accounts.
CONCLUSION: Unchecking Contacts does NOT remove them, contrary to Apple instruction, and as you wrote, there is no easy way to identify those contacts. You suggest I can hide them, but I did not see anything in that link about making them visible or not. Besides, that would not be satisfactory because for privacy I want them off my phone.
It appears I will have to go one-by-one and manually delete each non-iCloud contact.
Correct me if I am wrong. Thanks for your help.