North Sea Ferries was a ferry operator that operated services between the United Kingdom, Belgium and The Netherlands from 1965 until 1996.
North Sea Ferries formed in 1965 by a consortium of six European concerns (two British, two German and two Dutch) to operate a ferry service between Hull and Rotterdam Europoort. The original consortium members were Tyne Tees Steam Shipping Company (at that time part of Coast Lines), General Steam Navigation Company (majority owned by P&O), , A. Kirsten, Koninklijke Nederlandse Stoomboot-Maatschappij and Phs. van Ommeren.
Even before commencement of the Hull-Rotterdam service, North Sea Ferries were already exploring the potential for new routes between Britain and Europe. The Rotterdam service commenced operations in December 1965.
The remains of Coast Lines was acquired by P&O in 1971 and combined with the operations of General Steam Navigation to form the basis of P&O Ferries, with P&O therefore now directly holding an increased stake in the North Sea Ferries joint venture. A. Kirsten were declared bankrupt in October 1975.
By 1980, Van Ommeren and Argo Reederei were reported as having little interest in North Sea Ferries and a proposal was made for their remaining minority stakes to be sold to the other two remaining partners in the consortium (KNSM having merged with Nedlloyd). Thus, North Sea Ferries became jointly owned by Nedlloyd and P&O.
In 1987, the Princess Margaret Ferry Terminal was built under the operation of North Sea Ferries. The building is now under the ownership of Associated British Ports and is operated by P&O Ferries.
North Sea Ferries operated until 1996, when Nedlloyd's share of the venture was purchased by P&O giving them sole ownership. After this point operations were merged into P&O as P&O North Sea Ferries as part of the reorganisation of P&O Ferries arising from the merger of its Dover Straits services with those of Stena Line. P&O North Sea Ferries was then merged with P&O Ferries in 2003.
The former North Sea Ferries route between Hull and Rotterdam continues to be operated by P&O Ferries.
A service between Ipswich and Rotterdam was latterly operated by Luxembourg-based CLdN. This route was closed by the company in August 2012.
Sailings by P&O between Hull and Zeebrugge ceased in January 2021 due to the impact of the COVID-19 pandemic, although it was noted at the time of the closure announcement by Darren Procter of the RMT Union that it had been a "challenging route for a number of years".
In July 2025, P&O Ferries announced it was closing the route between Middlesbrough and Zeebrugge at the end of the month to focus on other routes.