Credited names: Valve

Oldest to newest, including sub-studios. Releases with unknown years appear last.

1. 1998

   • Half-Life

     Valve (developer)

2. 2004

   • Half-Life 2

     Valve (developer), Valve (publisher)

3. 2006

   • Half-Life 2: Episode One

     Valve (developer), Valve (publisher)

4. 2007

   • Half-Life 2: Episode Two

     Valve (developer), Valve (publisher)

5. 2020

   • Half-Life: Alyx

     Valve (developer), Valve (publisher)