Newegg offers downloads of Webroot SecureAnywhere 2017 AntiVirus 3-Device 1-Year License for Windows and Mac, model no. 25113-16, for $19.99. Coupon code "EMCRDCJ45" cuts the price to $9.99. That's the lowest price we could find by $10.
Also available is Bitdefender Antivirus Plus 2017 1-Device for Windows for $39.99. Coupon code "EMCRDCJ66" drops the price to $14.99. That's the lowest price we could find by $13. Both deals end April 3.