Invoice for Professional Services Rendered is a document used by professionals such as lawyers, accountants, consultants, and other service providers to bill clients for services rendered. The invoice typically includes the service provider’s name and contact information, the client’s name and contact information, a description of the services rendered, the total amount due, and payment terms. There are several types of Invoice for Professional Services Rendered. An Hourly Invoice is used when services are billed by the hour, and includes the hourly rate and number of hours worked. A Flat Rate Invoice is used when a single fee is charged for the services provided, regardless of the amount of time worked. A Progress Invoice is used for services provided over an extended period of time, and is typically broken down into installments. A Retainer Invoice is used to bill for services provided in advance, such as consulting or legal services. A Recurring Invoice is used to bill clients on a regular basis, such as monthly or quarterly. Finally, a Final Invoice is used to bill for services rendered and is typically the final invoice a client receives from a service provider.