Could MSC Cruises soon pass Carnival to become the world's second biggest cruise line?

There was a time when Carnival Cruise Line was the biggest cruise line in the world, when measured by the passenger capacity of its ships. But in recent years, it has lost that title to rival Royal Caribbean, as the latter line has added ever more and bigger ships.

Now Carnival is in danger of slipping to the No. 3 spot among the world's biggest cruise lines.

In an unexpected development being driven in part by coronavirus-related downsizing at Carnival, fast-growing MSC Cruises, which took delivery of yet another giant new vessel on Monday, increasingly appears on track to surpass the "fun ship" line as the world's second biggest cruise brand within the next three years.

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With 24 ships that have the capacity for 71,434 passengers, based on double occupancy, Carnival still is significantly larger than MSC Cruises. But its downsizing in recent months has significantly shortened its lead over MSC Cruises when it comes to passenger capacity -- and made its fall from the No. 2 spot among cruise lines almost inevitable.

In an effort to cut costs during the coronavirus-caused industry shutdown, Carnival has shed four older ships since July 2020, while adding one new ship, the 5,250-passenger Mardi Gras.

MSC Cruises, by contrast, hasn't shed a single ship and is adding two new vessels this year.

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With the addition of the 4,842-passenger MSC Virtuosa on Monday, MSC Cruises now has 18 ships with a capacity for 58,722 passengers, based on double occupancy. A second new MSC Cruises ship arriving in July, the 4,540-passenger MSC Seashore, will bring the line's passenger capacity to around 63,000, based on double occupancy.

While that's still roughly 8,000 fewer berths than Carnival's current total, an aggressive expansion plan already underway at MSC Cruises makes it likely that the line now will close that gap by the end of 2023.

MSC Cruises has four more ships on order for delivery from 2022 to 2025 that will collectively add around 20,000 more berths to its fleet. Carnival, by contrast, has just one more ship on order, the 5,250-passenger Carnival Celebration, due in 2022.

Related: The 9 most anticipated new cruise ships of 2021

Given current delivery schedules for the ships, the crossing point where MSC Cruises passes Carnival as the world's second biggest cruise line by passenger capacity now is likely to occur in 2023.

There are several factors that could affect such projections. For starters, MSC Cruises could remove some older ships from its fleet in the coming years, reducing its capacity. MSC Cruises also could ask its shipbuilder to slow or stop the construction of the new ships.

Alternately, Carnival could add additional ships to its fleet over the next few years.

But MSC Cruises has shown no desire to slow its capacity growth. In a press release Monday announcing the arrival of MSC Virtuosa, the line reiterated its plans to add all of the abovementioned ships by 2025.

Related: The ultimate guide to MSC Cruises

Carnival, meanwhile, appears to be entering a period where new ship orders are unlikely. In a recent conference call with Wall Street analysts, the CEO of Carnival's parent company, Carnival Corp., suggested that the company would focus in coming years on paying down debt instead of adding more vessels. The company has taken on a large amount of debt to stay afloat during the coronavirus crisis.

"We've stretched out the delivery schedule (of new ships), pushing out new build capital, and more importantly, we have just one ship for delivery in fiscal 2024 and just one ship for delivery in fiscal 2025," Carnival Corp. CEO Arnold Donald said, referring to two vessels that are on order not for the Carnival brand but for sister lines. "That will significantly reduce capital expenditures during those years, enabling us to pay down debt."

The growth at MSC Cruises, which is privately owned, is at a pace rarely seen in the industry. As recently as early 2017, the line had just 12 ships in operation. But it has added six giant new vessels in the past four years and now is on track to have 23 ships by 2025 with more than 80,000 berths, based on double occupancy.

As a result of the growth, MSC Cruises already has shot well ahead of such other major lines as Norwegian Cruise Line, Princess Cruises, Aida Cruises, Costa Cruises and Celebrity Cruises when it comes to passenger capacity.

It should be noted that even if Carnival, the line, falls in the ranks of biggest cruise brands, its parent company -- Carnival Corp. -- will remain the world's biggest cruise company. That's because Carnival Corp. owns not just Carnival but eight more major cruise brands including Princess, Costa, Holland America, Seabourn, Cunard and P&O Cruises.

Collectively, the nine Carnival Corp. brands have more than 230,000 berths and account for nearly 40% of the entire cruise business.

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