Peel Ports is to invest £10m in a new link-span bridge and a fourth berth at Heysham to handle larger ferries.
It will also create a new port entrance and improve IT and terminal operating systems.
Work will begin in November and is expected to be completed by October 2017.
It follows the opening of a new link road connecting the port and the M6, bypassing congestion in Lancaster, on 31 October.
Port director, David Huck said:
“This is a transformational time for Heysham port. Our major investment to increase capacity and flexibility will further strengthen the port’s role as a logistics hub for the region, particularly for services to Ireland and the Isle of Man. We’ve also built in an element of future-proofing, giving us the ability to accommodate projected volumes for many years to come.”