This issue occurs because the import file does not include an Account Name, which is required to create Accounts first. Since Contacts must be linked to an Account in Salesforce, they cannot be properly created and related without this information.
When a file only contains First Name, Last Name, and Email, there is no way to generate or associate an Account during a single-step import. This results in Contacts either not being linked correctly or becoming orphan records.
The recommended approach is to use a two-step import process:
First, update the file by adding an Account Name column (for example, a household name like “John Smith Household” or an organization name).
Import the file into the Account object using Import new records, mapping only the Account Name field and ignoring Contact-related fields.
Download the results file to obtain the generated Account IDs.
Next, import this results file into the Contact object, mapping First Name, Last Name, and Email to Contact fields, and mapping Account ID to link each Contact to the correct Account.
This ensures that Accounts are created first, followed by Contacts that are automatically linked to those Accounts.
Contacts cannot be created independently without an Account, so a two-step import (Accounts → Contacts) is the most reliable approach. Always verify that the input file includes an Account Name when the goal is to create and relate both Accounts and Contacts.