Modernized e-File (MeF) provides an option to e-file Corporate, Exempt Organization, Individual, Partnership, and Excise Tax Returns through the Internet. If you have already registered and applied as an e-file Provider, log in to MeF Internet Filing to transmit returns and retrieve acknowledgements. ** Note: IFA link for ATS only access until production shutdown / cut over period. https://la.www4.irs.gov/mef/ifa/internetFilingHome/ If you do not have an e-services user name or password or have not applied to be an Internet Filer, then you must go to the e-services Web page to register and apply to be an Internet Filer. For additional information on MeF Internet Filing, refer to Publication 4164, Modernized e-File (MeF) Guide for Software Developers and Transmitters PDF. To determine if the MeF systems are operational, refer to the Modernized e-File (MeF) Status Page.