Games like Signal
Games like Signal include Strange Horticulture, The Room, The Room Three, The Room Two, and Sally Face - Episode One. We matched them by the tags players give Signal on Steam (Atmospheric, Mystery, Text-Based, Puzzle, and Adventure): closest matches first, and among equally close ones the better-known games.

Strange Horticulture
Shared: Mystery · Puzzle · Atmospheric

The Room
Shared: Mystery · Atmospheric · Puzzle

The Room Three
Shared: Mystery · Puzzle · Atmospheric

The Room Two
Shared: Mystery · Atmospheric · Puzzle

Sally Face - Episode One
Shared: Puzzle · Mystery · Atmospheric

Strange Antiquities
Shared: Mystery · Puzzle · Atmospheric

Outer Wilds
Shared: Mystery · Atmospheric · Adventure

What Remains of Edith Finch
Shared: Atmospheric · Mystery · Story Rich

The Room 4: Old Sins
Shared: Mystery · Puzzle · Adventure

OneShot
Shared: Atmospheric · Story Rich · Puzzle

The House of Da Vinci
Shared: Mystery · Puzzle · Atmospheric

Return of the Obra Dinn
Shared: Mystery · Atmospheric · Puzzle

Firewatch
Shared: Atmospheric · Adventure · Mystery

The Wolf Among Us
Shared: Adventure · Story Rich · Choices Matter

INSIDE
Shared: Atmospheric · Dark · Story Rich

Servant of the Lake
Shared: Puzzle · Adventure · Atmospheric

Rusty Lake Paradise
Shared: Puzzle · Atmospheric · Adventure

Boxes: Lost Fragments
Shared: Mystery · Puzzle · Atmospheric

Cube Escape Collection
Shared: Mystery · Puzzle · Atmospheric

Papers, Please
Shared: Puzzle · Atmospheric · Point & Click

Death and Taxes
Shared: Choices Matter · Story Rich · Puzzle

Little Nightmares
Shared: Atmospheric · Adventure · Puzzle

Fran Bow
Shared: Puzzle · Adventure · Atmospheric

Zero Escape: The Nonary Games
Shared: Mystery · Puzzle · Story Rich