Invoice vs Sales Order

An invoice and a sales order are two important documents used in financial transactions within the realm of business. While they share similarities, they serve different purposes and play distinct roles in the sales process.


An invoice is a commercial document that represents a formal request for payment from a seller to a buyer, usually after goods or services have been provided. It serves as a record of the transaction and provides a breakdown of the quantity, price, and description of the items sold or services rendered.

On the other hand, a sales order is a document generated by a buyer to request the delivery of goods or services from a seller. It is essentially a purchase order issued by the customer and acts as a formal agreement to proceed with the transaction. A sales order outlines the specific items, quantities, prices, and delivery details requested by the buyer.

Key Differences:

1. Timing:

The primary distinction between an invoice and a sales order lies in their timing within the sales cycle. A sales order is created before goods or services are delivered, serving as a precursor to the actual transaction. Conversely, an invoice is created after the completion of the transaction, once the goods have been delivered or services rendered.

2. Purpose:

A sales order is primarily used to communicate the buyer’s intent to purchase and initiate the order fulfillment process. It outlines the terms of the agreement, including item details, quantities, agreed-upon prices, and expected delivery or service dates. An invoice, on the other hand, serves as a formal request for payment, providing the buyer with a record of the amount owed for the goods or services received.

3. Legal Status:

While a sales order is not a legally binding document, it serves as an internal document for the buyer and the seller, guiding the fulfillment process and providing a reference for any disputes or discrepancies that may arise. Conversely, an invoice holds legal weight as it represents the seller’s demand for payment and can be used as evidence in case of non-payment or legal disputes.

4. Financial Impact:

A sales order does not directly impact the financial statements of either party since it is simply a record of the buyer’s intent to purchase. It does not affect revenue or accounts receivable. Conversely, when an invoice is issued and accepted, it becomes an account receivable for the seller, impacting both revenue and accounts receivable in their financial statements.


In summary, while both an invoice and a sales order are integral parts of the sales process, they serve different purposes and are generated at different stages. A sales order represents the buyer’s intent to purchase, while an invoice is a request for payment from the seller. Understanding the distinctions between these documents is crucial for maintaining accurate financial records and ensuring smooth business transactions.

This glossary is made for freelancers and owners of small businesses. If you are looking for exact definitions you can find them in accounting textbooks.

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