General information and technical guidance for electronic return originators, software developers and transmitters who participate in Modernized e-File (MeF) is provided below. General information Assurance Testing System (ATS) Foreign country code listing Recommended names and descriptions for PDF Files SSL certificates Updated on October 24, 2024: These are effective from October 28, 2024. ATS certificates ZIP Production certificates ZIP Publications Publication 1220, Specifications for Electronic Filing of Forms 1097, 1098, 1099, 3921, 3922, 5498, and W-2G PDF Publication 1345, Handbook for Authorized IRS e-file Providers of Individual Income Tax Returns PDF Publication 1436, Assurance Testing System (ATS) Guidelines for Modernized e-File (MeF) Individual Tax Returns PDF Publication 3112, IRS e-File Application and Participation PDF Publication 4163, Modernized e-File (MeF) Information for Authorized IRS e-file Providers for Business Returns PDF Publication 4164, Modernized e-File (MeF) Guide for Software Developers and Transmitters PDF Publication 5078, Modernized e-File (MeF) Test Package (Business Submissions) PDF Publication 5446, Modernized e-File (MeF) Submission Composition Guide PDF Publication 5594 Standard Postal Service State Abbreviations and ZIP Codes PDF Publication 5830, Modernized e-File (MeF) IS State and Trading Partners Reference Guide PDF User guides Automated Enrollment (AE) PDF (revised 10/2017) Application-to-application (A2A) toolkit The A2A MeF Software Development Kit (SDK) Toolkit provides software tools and documentation making it easier to build the A2A Client Application for transmitters and states. The toolkit will make it much easier to set up the service requests you need to develop to access the MeF system. The A2A Toolkit is available to those transmitters and states interested in using the Modernized e-File (MeF) system to send or receive returns. If you are interested in receiving the toolkit, please send an e-mail to the MeF mailbox to request a copy. Please put A2A Toolkit in the subject line. If you are using Strong Authentication in your transmissions, you must purchase Strong Authentication Certificates. Information on the Strong Authentication Certificates and where they can be purchased can be found at the following sites: IdenTrust ORC It will take between 7 to 14 days for a digital certificate to be issued after you have notarized your paperwork and submitted it to the company. It is imperative that affected contractors keep their digital certificates current. An expired digital certificate will delay the ability to submit. Back to MeF Program information Back to E-file options
