Games like Oxygen Not Included
Games like Oxygen Not Included include RimWorld, Prison Architect, Factorio, Frostpunk, and Space Haven. We matched them by the tags players give Oxygen Not Included on Steam (Colony Sim, Base Building, Survival, Resource Management, and Building): closest matches first, and among equally close ones the better-known games.

RimWorld
Shared: Colony Sim · Base Building · Survival

Prison Architect
Shared: Base Building · Colony Sim · Building

Factorio
Shared: Base Building · Resource Management · Survival

Frostpunk
Shared: Survival · Resource Management · Colony Sim

Space Haven
Shared: Colony Sim · Base Building · Survival

Dyson Sphere Program
Shared: Base Building · Resource Management · Building

Manor Lords
Shared: Base Building · Building · Colony Sim

Kingdoms and Castles
Shared: Colony Sim · Resource Management · Management

Dwarf Fortress
Shared: Colony Sim · Base Building · Survival

Against the Storm
Shared: Base Building · Building · Colony Sim

Banished
Shared: Colony Sim · Survival · Singleplayer

Planetbase
Shared: Colony Sim · Base Building · Survival

Space Engineers
Shared: Survival · Building · Base Building

Ratopia
Shared: Colony Sim · Base Building · Building

IXION
Shared: Survival · Colony Sim · Resource Management

Empires of the Undergrowth
Shared: Base Building · Colony Sim · Building

Settlement Survival
Shared: Colony Sim · Survival · Building

They Are Billions
Shared: Colony Sim · Base Building · Survival

Endzone - A World Apart
Shared: Survival · Base Building · Colony Sim

Workers & Resources: Soviet Republic
Shared: Base Building · Building · Colony Sim

Norland
Shared: Base Building · Colony Sim · Building

Satisfactory
Shared: Base Building · Building · Resource Management

The Crust
Shared: Base Building · Colony Sim · Resource Management

Ostriv
Shared: Colony Sim · Base Building · Building