In Odoo, you can create the following types of invoices
Basic Invoice Types
Customer Invoices: These are the main invoices issued to customers for sold goods or services.
Customer Refunds (Credit Notes): Used to refund customers in case of product returns or invoice errors.
Supplier Invoices: Created to record bills from suppliers for received goods or services.
Supplier Refunds (Debit Notes): Used to process refunds from suppliers in case of product returns or invoice errors.
Invoicing Methods
Odoo also supports various invoicing methods:
Fixed Price Invoicing: Suitable for businesses with fixed prices for products or services.
Milestone-Based Invoicing: Used for projects with multiple stages, allowing invoicing upon completion of specific milestones.
Delivered Quantity Invoicing: Appropriate for partial deliveries or services provided outside the schedule.
Subscription-Based Invoicing: Automates invoicing for regular services or products.
Specialized Invoice Types
Additionally, specialized invoice types are available:
Tax Invoices
Retail Invoices
These can be configured using additional modules.
When creating an invoice, you can select the appropriate type based on your business needs. The invoice will initially be in "Draft" status and will have no accounting impact until it is validated, at which point Odoo assigns it a unique number from a defined sequence.