Amazon Kindle Goodreads - all genres
Indie Authors International - all genres
eBook World** - all genres
Self-Published Crime Fiction Writers - mystery, crime, thriller
Crime,Thriller, Mystery Readers' Café - mystery, crime, thriller
Kindle Unlimited - all genres in the Kindle Unlimited program
Thriller Mystery Suspense Book Club - mystery, crime, thriller
Thrillers Killers & Suspense - mystery, crime, thriller
Kindle/ Book Club - all genres
Mystery & Thriller Publicity Book Club - mystery, crime, thriller
Free Kindle Books - all genres as long as the book is free
The Apocalyptic Book Club - dystopian
Kindle Krazy! Authors Actively Seeking Readers - all genres
Band of Dystopian Authors and Fans* - dystopian
Dystopian Fantasy Bookworms* - dystopian
Ebook & Book Ads and Promotions - all genres
Indie Writer Books and Self Promotion - all genres
Book Reviews and Promotion - all genres
* special – see requirements before posting.
** has to be approved before they’ll let the ad post
Read the pinned posts before you join the group to make sure it's a group you really want to be in and then follow their guidelines before you post ads to them. Most of them don't want you to post more than once a day, which is only right. Otherwise, it's spammy and no one wants that.
I've had some minor successes here and there with these groups. Can't hurt, right?
Oh, and be prepared for your newsfeed to blow up with book ads and recommendations. If you're like me, they'll be both annoying and exciting. I mean, 'gah, so many book posts' and 'hey, previously unheard of books to read!'