I want to associate a unique number with my customer. How can I do this in Zoho Books?

To enable Customer / Vendor number:

1. Click the Settings icon at the top right corner.
2. Choose Customers and Vendors from Preferences.
3. Scroll down and mark the checkbox for Enable Customer Number to activate the option for customers, and mark the checkbox for Enable Vendor Number to activate the option for vendors.

Now, you can opt for any one of the options:

• Retain existing vendor / customer numbers: If you’ve maintained customer / vendor numbers using a custom field until now, you can choose to copy the existing numbers to the new Customer / Vendor Number field.
• Generate new vendor / customer numbers: You can configure a series to generate customer / vendor numbers automatically for all your existing customers or vendors.

4. Save the preference.