Contacts on iOS not showing on iCloud.com

Try Settings/Your Name/iCloud and slide off Contacts syncing. Wait a few minutes and then slide syncing on. Allow time for syncing to occur.

Last resort - have you tried signing out of iCloud, restarting the device, and then signing back in?

See the Apple Support article below. 

Contacts, Calendars, or Reminders - Get help using iCloud.  

Hey there, lgoler!

Thanks so much for using Apple Support Communities.

Syncing your contacts between all of your devices is such a great feature that iCloud offers. We're happy to see if we can figure it out with you.

To start, one of the more common reasons we see for this issue is the contacts being stored in another account besides iCloud. Sometimes it can be easy to not realize that the contacts are associated with a different account. The contacts stored in a Gmail account, for example, won't necessarily sync via iCloud to your other devices. The good news is that it should be super easy to check which account those contacts are syncing with.

This article is a great resource: Manage and delete contacts on your iPhone, iPad, or iPod touch

We hope that this information is helpful.

​Have a great day!