Shanghai Waigaoqiao Shipbuilding (SWS) has reeled in an order from Seaspan Corp for 10 containership newbuildings worth around $860m.

Shipbuilding sources said Seaspan has contracted Chinese state-owned SWS to build the 7,000-teu series for delivery in 2024, backed by charters to Singapore-based Ocean Network Express (ONE).

Seaspan has opted for vessels that will run on conventional marine fuels, and the company is said to be paying around $86m per ship.

News that Hong Kong and Vancouver-based Seaspan were planning to order the 10 containerships at SWS was first reported in TradeWinds in June.

Shipbuilding sources said Seaspan did not sign up for the 10 newbuildings on speculation.

It has booked the containerships on the back of long-term charters with liner operator ONE, a join venture of Japanese giants NYK Line, K Line and Mitsui OSK Lines. The charter period and rate were not disclosed. However, the sources said ONE has fixed the boxships for more than 10 years.

Officials at SWS were not immediately available for comment. A Seaspan spokesman said the outfit does not comment on market speculation and would only discuss publicly disclosed developments. ONE did not reply to emails seeking confirmation on the charters.

Seaspan’s latest newbuilding order at SWS adds to a shopping spree for 7,000-teu ships that has now seen the New York-listed tonnage provider sign up for 25 such vessels this year. The earlier 15 newbuildings were dual-fuel boxships booked at Yangzijiang Shipbuilding for delivery between the last quarter of 2023 and the end 2024.

Seaspan was reported to be paying $106m each for the ships that can run on both LNG and conventional marine fuel. It has ordered the newbuildings on the back of charters with liner operator Zim.

The Israeli liner company has fixed the containerships for a minimum of 12 years. The value of the charter contracts for the 15 ships is estimated at $2.25bn.

According to Clarksons’ Shipping Intelligence Network, 51 ships in the 7,000-teu size range are on order at shipyards, including Seaspan’s latest 10 vessels at SWS.

Shipbuilding sources said there is still a strong level of inquiry in this size class, as the ships are flexible and can be used for service routes in the Far East Asia-to-Middle East, as well as north-south trades.

Hamburg Sud and Mediterranean Shipping Co are said to be looking to charter the 7,000-teu boxships.

Seaspan chief executive Bing Cheng recently said there is strong customer interest in this containership size, and he sees the vessels "to be the natural successor to the ageing global pool of conventional vessels in the 4,000-teu to 9,000-teu range, where relatively little fleet renewal has taken place".