For authors ↗

DISCOVER YOUR NEXT FREE READ

Free Science Fiction Books

Explore free science fiction, from space opera and alien encounters to dystopian futures and time travel. Visit a book page to discover its story and retailer options.

24 free books · showing 1–24

Clear filters
2156 cover

Science Fiction · Dystopian & Post-Apocalyptic

2156

The ReLife Project · Book 1

C.M. Dancha

Get the Free BookAudiobook available
28 Days cover

Science Fiction · Dystopian & Post-Apocalyptic

28 Days

The Reluctant Doorkeeper Trilogy · Book 1

Sue Parritt

Get the Free BookAudiobook available
Family cover

Science Fiction · Dystopian & Post-Apocalyptic

Family

Reacher Short Stories · Book 1

L.E. Fitzpatrick

Get the Free BookAudiobook available

About Free Science Fiction Books

Free science fiction books imagine possibilities beyond the world we know, from distant star systems to altered societies and journeys through time. Technology, exploration and the consequences of change can shape both the adventure and its underlying questions.

Browse space opera, dystopian and post-apocalyptic fiction, time travel, alien encounters, and science fiction thrillers. Whether you prefer large-scale adventures or closer-to-home speculation, the descriptions can point you toward your next free read.