diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs b/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs
index 1adf17dab3..c26383fb47 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs
@@ -196,7 +196,7 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 					Port3E = 0xF7;
 
 				if (BiosRom == null && game["RequireBios"])
-					CoreComm.Notify("BIOS image not available. This game requires BIOS to function.");
+					throw new MissingFirmwareException("BIOS image not available. This game requires BIOS to function.");
 				if (SyncSettings.UseBIOS && BiosRom == null)
 					CoreComm.Notify("BIOS was selected, but rom image not available. BIOS not enabled.");
 			}