IFRS 15 is not an invoice-recognition rule. Revenue is recognised when, or as, an entity satisfies a performance obligation by transferring control of a promised good or service to a customer. A contract, invoice, tax document or cash receipt may be important evidence, but none of those documents on its own determines when revenue has been earned. This guide turns the five-step model into a practical framework for students, finance teams and reviewers. It also shows why billing, accounting revenue, EFRIS or VAT records and income-tax reporting may legitimately move at different times—and why those differences still need disciplined reconciliation. IFRS 15 in brief IFRS 15 Revenue from Contracts with Customers establishes the principles for reporting the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. Its core principle is that revenue should depict the transfer of promised goods or services to a customer in an amount that r...