A proforma invoice is a preliminary invoice that is sent to a buyer before a sale is confirmed. Learn the difference between a proforma invoice and an invoice , the fields to include, and how to create one with Zoho Invoice . Works Online & Offline. A Complete GST Software for All Your Accounting Needs. Professionally designed Proforma Invoice formats. Download Now! Discover the essentials of proforma invoices , including their uses, benefits, and how they streamline pre-invoicing processes for businesses. An invoice is a commercial tool that typically contains the total amount for services or products due to the customer whereas a pro forma invoice is merely a seller’s declaration to provide services or products to the customer on a set date and time.