Settings > Passwords and Accounts > AutoFill Passwords Make sure it's enabled and uncheck "iCloud Keychain" while leaving "1Password" checked. It'll basically

Settings > Passwords and Accounts > AutoFill Passwords Make sure it's enabled and uncheck "iCloud Keychain" while leaving "1Password" checked. It'll basically make it your default password manager. Most apps that I use handle this well. Some (E-trade) don't seem to have the implementation quite right.