HEAD OF ZEUS
HoZ won independent publisher of the year 2017, and it’s easy to see why. They publish genre fiction, children’s books and narrative non-fiction, including authors such as C. J. Box and Graham Masterton. They do accept unsolicited submissions via a submissions portal, but when it gets very busy they temporarily close. Check by periodically. Keep in mind it can take many months to get a reply. I waited six. This is their current website: http://headofzeus.com/ but they will be updating it shortly to this: https://uat.headofzeus.com/home?_ga=2.135399476.466581387.1566109317-1495559976.1561452066
JOFFE BOOKS
One of the UK’s leading independent publishers of crime, thriller and mystery fiction, Joffe Books publishes Helen H. Durrant, Joy Ellis and Faith Martin amongst others. They accept submissions from unagented authors – even if you’ve self published your book (a lot of publishers don’t).
Check out their submission guidelines here: http://www.joffebooks.com/submissions
BLACK AND WHITE
An independent publisher based in Scotland. They publish most genres of fiction and some non-fiction. Their children’s book imprint Itchy Coo sounds like thrush. Submissions are via a contact form, and they can take up to six months to make a decision.
http://blackandwhitepublishing.com/submissions
BLOODHOUND BOOKS
A leading independent publisher of crime, thriller and mystery fiction, authors include the bestselling Rob Sinclair and Betsy Reavley. Submissions close temporarily if they’re too busy. Your MS should be at least 60,000 words, and they aim to respond within four weeks.
https://www.bloodhoundbooks.com/submissions
POLIS BOOKS
Polis Books is currently accepting submissions of thrillers, women’s and genre fiction and non-fiction in the areas of humour, pop culture and true crime. They aim to make a decision in 12 weeks.
http://www.polisbooks.com/submissions/
CROOKED LANE
Founded in 2014, Crooked Lane Books publishes crime, thriller and mystery fiction. They will reply within two weeks if they’re interested in your submission.
http://www.crookedlanebooks.com/contact/
SEVENTH STREET BOOKS
A publisher of thrillers and mystery fiction, Seventh Street Books publishes the award-winning Lori Rader-Day and Allen Eskens. Submit the full MS and a three-paragraph synopsis.
https://www.seventhstreetbooks.com/submission-guidelines/
VERVE BOOKS
A small digital publisher of crime, thriller and commercial fiction. Submissions are via contact form, and they aim to reply within three months.
http://www.vervebooks.co.uk/submit.php
SAPERE BOOKS
A digital publisher looking for Crime Fiction, Mysteries, Thrillers, Women’s Fiction, Romantic Fiction, Historical Fiction, Action and Adventure (Military, Naval and Aviation Fiction) and History.
https://saperebooks.com/about/submissions/
KENSINGTON PUBLISHING
One of the top independent publishers in the United States, Kensington Publishing accepts submissions in all genres except children’s, YA and poetry. As per usual US guidelines, only submit a query in the first instance, no manuscript. They will reply within three months if interested.
https://www.kensingtonbooks.com/page.aspx/submissions
Best of luck with your submissions! As a thriller writer myself, I know what a daunting, frustrating, infuriating task submitting to publishers and agents is. Your initial submission, which usually consists of a cover letter, synopsis and sample chapters, needs to be perfect. Why not check out my proofreading services? £40 for a proofread of your cover letter, synopsis and first 10,000 words of your MS.
Also, be sure to check out my highly rated thrillers, MEMORIES UNSPEAKABLE and SHARK BAIT! SHARK BAIT was a finalist in A.M. Heath's Criminal Lines Competition 2015 and reached the acquisition boards of both Orion and Harlequin Harper Collins.