Located in water depths around 15m, 8km east of Spurn Point off the coast of the East Riding of Yorkshire, the project is the final phase of construction and is scheduled to be fully operational soon.
The wind farm features 73 V112-3MW turbines that can generate electricity to serve around 170,000 homes in the UK.
E.ON management board member responsible for renewables business Bernhard Reutersberg said: "E.ON is well on its way toward making offshore wind power even more competitive and reducing power-generation costs to less than €100 per megawatt-hour.
"We’re superbly positioned for future auctions in relevant European markets."
The 700m ($1.17bn) wind farm will use an offshore cable to transfer the generated power to the National Grid.
E.on Humber Gateway project manager Matthew Swanwick said: "This is the last stage of the major construction phase and the culmination of more than three years’ offshore construction work which began in early 2012 starting with work at the onshore substation."
Separately, E.on is developing the Rampion offshore wind farm in the UK and Amrumbank West offshore farm in the German North Sea.
