Retainer Invoice Template for England and Wales

A retainer invoice is a specialised billing document that allows service providers to charge clients for ongoing professional services under a retainer agreement. Unlike standard invoices for completed work, retainer invoices establish regular payment schedules for services that will be provided over time, creating predictable cash flow for businesses while securing professional services for clients.

When do you need this document?

You need a retainer invoice when providing professional services on an ongoing basis, such as legal advice, consulting, marketing services, or technical support. This document is particularly important when you've agreed to provide a certain number of hours or level of service each month in exchange for regular payments. Retainer invoices are commonly used by solicitors, accountants, IT consultants, and creative agencies who maintain long-term client relationships. You'll also need this document when transitioning from project-based billing to ongoing service arrangements, or when clients request predictable monthly costs for budgeting purposes.

Key legal considerations

Your retainer invoice must clearly specify the scope of services covered under the retainer agreement to avoid disputes about what work is included versus what requires additional billing. Include detailed payment terms that comply with the Late Payment of Commercial Debts Act 1998, which entitles you to statutory interest on late payments after 30 days for business-to-business transactions. Ensure your invoice clearly distinguishes between retainer fees for ongoing availability and actual work performed, as this affects how services are delivered and billed. Consider including clauses about unused retainer credits, whether they roll over to subsequent periods or are forfeited, and how additional work beyond the retainer scope will be charged.

Legal requirements in England and Wales

Under the Companies Act 2006, your retainer invoice must display your company's registered name, registration number, and registered office address if you're a limited company. The Value Added Tax Act 1994 requires VAT-registered businesses to show their VAT number, the VAT rate applied, and the total VAT amount on all invoices over £100. Your invoice must include a unique invoice number, issue date, and clear description of the services covered by the retainer. Payment terms must specify the due date and available payment methods, with statutory interest rates clearly stated for late payments as required by the Late Payment of Commercial Debts Act 1998. If providing services to consumers rather than businesses, ensure compliance with the Consumer Rights Act 2015 regarding service quality standards and clear terms about the retainer arrangement.