Experimental aircraft pilot reported losing engine power mid-flight and safely landed in an area that was not the airport. Upon further troubleshooting the pilot realized the fuel shutoff valve was closed; resulting in the engine not receiving any fuel; a mistake that was not caught during preflight.

Narrative

I was going for a personal flight nothing specific in mind. The specific mistake happened during my preflight. I missed the fact that the fuel shutoff valve was closed. I believe this happened because I got complacent. I typically just always leave the fuel shutoff valve open. However; I hadn't flown the plane in awhile and forgot to check the fuel shutoff valve pre-flight. Everything went normal until about 5 minutes after departure cruising at or just below about 1;500 ft. MSL. The engine began to stutter; I tried flipping on the boost pump; and immediately started planning where I would put it down if I lost engine power. As I was doing this the engine died. I had two spots in mind that I could safely land. I tried restarting the engine and troubleshooting on the way down to no avail. My main focus was getting to the ground safely. I could not make it to an airport. I picked a spot and safely landed the aircraft; away from people and in a spot the plane did not get damaged. After I landed and was safe I did more troubleshooting and realized the fuel shutoff valve was closed and my engine died because it was not getting fuel despite having plenty. After I opened the fuel shutoff valve the plane started and ran normally. I can avoid this in the future by not being complacent and assuming the fuel shutoff valve would be in the open position the way I normally leave it or by creating and using [a] preflight checklist that includes checking the fuel shutoff valve.