Yes, you can associate deals with contacts without creating an account in Zoho CRM.
If your organization deals directly with customers in a B2C scenario, the best way to associate deals without an account is to disable the Accounts module in your CRM account, since accounts represent companies that you do business with, and this does not apply for B2C.
To disable the Accounts module:
Go to Setup in your CRM account.
Select Modules and Fields under Customization.
Click Organize Modules.
Uncheck the Accounts module on the Organize Modules page.
Click Save.
Once the Accounts module has been disabled, the Account Name field will not appear on the Deals page when you associate a deal with a contact.
The Account Name field also won't be auto populated when converting leads to contacts.
If your organization deals with other businesses and with individual customers (both B2B and B2C), disabling the Accounts module won't work. In this case, you need to make the Company and Account Name fields non-mandatory in both the Leads and Deals modules. This will allow you to save records without filling in those fields.
To make the fields non-mandatory:
Go to the Setup in your CRM account.
Select Modules and Fields under Customization.
Go to the Edit Layout page for the Deals module.
Click on the three dots icon next to the Account Name section.
Uncheck the Mark as required field.
Save the layout.
Note:
If you want to be able to associate a deal with a lead as you are converting it into a contact, follow the steps above but instead of the Account Name field, mark the Company field as non-mandatory.
Don't fill in the Company name while adding a lead. When converting a lead to a contact, just check the Create a new Deal for this Contact box, fill in the details, and click Convert. You have now successfully associated a deal with a contact without creating an account.