From a Q&A session https://www.nasa.gov/content/goddard/qa-on-noaas-dscovr-mission/ https://www.nasa.gov/content/goddard/qa-on-noaas-dscovr-miss... The mission

From a Q&A session https://www.nasa.gov/content/goddard/qa-on-noaas-dscovr-mission/ https://www.nasa.gov/content/goddard/qa-on-noaas-dscovr-miss... The mission is slated for 2 years, and they have fuel for 5. I also happen to know that they reached L1 faster than anticipated thanks to a really nice insertion from the SpaceX Falcon 9 launch vehicle. This means that the operational life might be even longer, but I haven't found any sources for what that might be.