According to the 2016 General Instructions for Certain Information Returns:

• New Due Date for Forms 1099-MISC Using Box 7 — January 31, 2017 is now the due date for filing Forms 1099-MISC when reporting nonemployee compensation payments in box 7. Otherwise, file on paper by February 28, 2017, or file electronically by March 31, 2017. (The due dates for furnishing payee statements remain the same.)
• Electronic Filers must use the FIRE System. The IRS has included a “First Time Filers Quick Reference Guide” in Publication 1220 (page 2).
• Extensions — A 30-day extension must be requested by the due date of the return. Under certain hardship conditions, an additional 30-day extension can be requested. For more information, go to https://www.irs.gov/pub/irs-pdf/i1099gi.pdf (page 6).

More detailed information is available at https://www.irs.gov/pub/irs-pdf/p1220.pdf.