Games like One More Island
Games like One More Island include Oxygen Not Included, Frostpunk, Prison Architect, Settlement Survival, and Manor Lords. We matched them by the tags players give One More Island on Steam (Exploration, City Builder, Colony Sim, Building, and Survival): closest matches first, and among equally close ones the better-known games.

Oxygen Not Included
Shared: Colony Sim · Survival · Building

Frostpunk
Shared: City Builder · Survival · Colony Sim

Prison Architect
Shared: Building · Colony Sim · City Builder

Settlement Survival
Shared: City Builder · Colony Sim · Building

Manor Lords
Shared: City Builder · Building · Base Building

IXION
Shared: City Builder · Survival · Colony Sim

Kingdoms and Castles
Shared: City Builder · Colony Sim · Management

RimWorld
Shared: Colony Sim · Survival · Base Building

Cities: Skylines
Shared: City Builder · Building · Management

Against the Storm
Shared: City Builder · Building · Colony Sim

Workers & Resources: Soviet Republic
Shared: City Builder · Building · Base Building

Banished
Shared: City Builder · Colony Sim · Survival

Empires of the Undergrowth
Shared: City Builder · Colony Sim · Building

Space Haven
Shared: Colony Sim · Survival · Base Building

Dwarf Fortress
Shared: Colony Sim · City Builder · Base Building

Ratopia
Shared: Colony Sim · Building · Survival

Norland
Shared: City Builder · Colony Sim · Building

Ostriv
Shared: City Builder · Colony Sim · Building

Farthest Frontier
Shared: City Builder · Building · Colony Sim

Pharaoh™: A New Era
Shared: City Builder · Building · Colony Sim

Cities: Skylines II
Shared: City Builder · Building · Management

Endzone - A World Apart
Shared: City Builder · Survival · Colony Sim

Timberborn
Shared: City Builder · Colony Sim · Building

Foundation
Shared: City Builder · Building · Management