What Google said in December 2018
We announced our decision to shut down Google+ for consumers in April 2019 due to
low usage and challenges involved in maintaining a successful product that meets consumers' expectations. We want to thank you for being part of Google+ and provide next steps, including how to download your photos and other content.
Google+ account and any Google+ pages
On April 2nd, your Google+ account and any Google+ pages you created will be shut down and we will begin deleting content from consumer Google+ accounts. Photos and videos from Google+ in your Album Archive and your Google+ pages will also be deleted. You can download and save your content, just make sure to do so before April. Note that photos and videos backed up in Google Photos will not be deleted.
How long will it take?
The process of deleting content from consumer Google+ accounts, Google+ Pages, and Album Archive will take a few months, and content may remain through this time. For example, users may still see parts of their Google+ account via activity log and some consumer Google+ content may remain visible to G Suite users until consumer Google+ is deleted.
As early as February 4th, you will no longer be able to create new Google+ profiles, pages, communities or events.
See the full FAQ for more details and updates leading up to the shutdown.
What to do
Moderators Google+ Communities
If you're a Google+ Community owner or moderator, you may download and save your data for your Google+ Community. Starting early March 2019, additional data will be available for download, including author, body, and photos for every community post in a public community. Learn morener
Login
If you sign in to sites and apps using the Google+ Sign-in button, these buttons will stop working in the coming weeks but in some cases may be replaced by a Google Sign-in button. You'll still be able to sign in with your Google Account wherever you see Google Sign-in buttons.
Site owners
If you've used Google+ for comments on your own or other sites, this feature will be removed from Blogger by February 4th and other sites by March 7th. All your Google+ comments on all sites will be deleted starting April 2, 2019. Learn more
G Suite customer
If you're a G Suite customer, Google+ for your G Suite account should remain active. Contact your G Suite administrator for more details. You can also expect a new look and new features soon. Learn more
Developer
If you're a developer using Google+ APIs or Google+ Sign-in, click here to see how this will impact you.