EAOW is a 50-50 joint venture between the UK's ScottishPower Renewables and Swedish energy utility Vattenfall Wind Power, which has been awarded rights to develop 7.2GW of wind power off England's east coast.
This is part of the Crown Estate's round three offshore wind programme, which identified 33GW of wind capacity in UK waters.
Coastline will undertake a series of surveys to provide information to support the environmental impact assessment and enable preliminary cable installation for East Anglia 3 and East Anglia 4.
The company will deploy its own survey vessel MV FlatHolm and a specialist team of hydrographic surveyors.
Andy Johnson, Coastline divisional manager, said: "I am pleased Coastline was able to win such a prestigious contract against some pretty stiff competition."