Update 6 2016.04.07 Alternative MSO Download Site In addition to download the latest release of Microsoft Office for Mac on this post, Farrukh recommended a very nice website where you can download Microsoft Office for Mac, including all legacy versions and Microsoft AutoUpdate.app (MAU). Note that this is not an official stable version.
Update 7 2016.07.03 Insider Fast Channel Update – Office for Mac 15.25.0 (64bit) Microsoft released a new 64bit version of Office for Mac to Office Insiders. Update 9 2018.09.26 Support Office 2019 for Mac now. However, you can download my VL patch to avoid the requirement of Office 365 subscription.
You are still required to have a Office 365 subscription in order to enable full features. Microsoft released a new version (16.17.x) of Office 2019 for Mac.