It is a document that exists only in a digital environment, it is issued and stored electronically, it came into force on September 15, 2006, and came to replace invoices that had been printed until then. The NF-e showcased a great advance, and it came to make life easier for taxpayers and for all inspection activities conducted by the government. The mandatory use of the NF-e includes all ICMS taxpayers that meet at least one of the situations described below: • That develops industrial activity • That develops wholesale or distribution activity • That transports goods to another State • That supplies goods to the Public Administration. All companies of all sizes are required to issue the Electronic Invoice, including those that have opted by the Simples Nacional Taxation Regime.