Games like Add Astra
Games like Add Astra include FTL: Faster Than Light, Sid Meier's Civilization®: Beyond Earth™, Cosmoteer: Starship Architect & Commander, XCOM: Enemy Unknown, and Iron Marines. We matched them by the tags players give Add Astra on Steam (Education, Racing, Aliens, Sci-fi, and Space): closest matches first, and among equally close ones the better-known games.

FTL: Faster Than Light
Shared: Space · Sci-fi · Strategy

Sid Meier's Civilization®: Beyond Earth™
Shared: Sci-fi · Space · Strategy

Cosmoteer: Starship Architect & Commander
Shared: Sci-fi · Singleplayer · Space

XCOM: Enemy Unknown
Shared: Sci-fi · Aliens · Strategy

Iron Marines
Shared: Sci-fi · Singleplayer · Strategy

ENDLESS Space™ - Definitive Edition
Shared: Sci-fi · Space · Strategy

Stellaris
Shared: Space · Sci-fi · Strategy

ENDLESS Space™ 2
Shared: Sci-fi · Space · Strategy

XCOM®: Chimera Squad
Shared: Aliens · Strategy · Singleplayer

Kerbal Space Program
Shared: Space · Education · Singleplayer

Sid Meier's Starships
Shared: Space · Sci-fi · Strategy

Aliens: Dark Descent
Shared: Strategy · Sci-fi · Aliens

Heat Signature
Shared: Space · Sci-fi · Indie

Terraforming Mars
Shared: Space · Strategy · Board Game

911 Operator
Shared: Singleplayer · Strategy · Casual

SpaceEngine
Shared: Sci-fi · Space · Casual

Gaia Project
Shared: Casual · Strategy · Aliens

STAR WARS™ Empire at War - Gold Pack
Shared: Sci-fi · Space · Strategy

Space Pirates and Zombies
Shared: Space · Sci-fi · Indie

Alien: Isolation
Shared: Aliens · Sci-fi · Space

Defense Grid: The Awakening
Shared: Sci-fi · Aliens · Singleplayer

Prey
Shared: Sci-fi · Space · Singleplayer

Reassembly
Shared: Space · Strategy · Singleplayer

Tharsis
Shared: Space · Singleplayer · Board Game