Having announced it was leaving the alliance in November 2018, China Southern Airlines (CZ, Guangzhou) officially parted company with Skyteam on January 1, 2020, after a year of transition works to separate the two entities. The carrier will maintain deep cooperation with Skyteam members, preserving many of the ties that almost amounts to a de-facto membership of the alliance.

In an announcement posted on its website shortly before it left the alliance, China Southern said that it would continue to codeshare and maintain frequent flyer cooperation with 14 of the 19 SkyTeam members including Xiamen Airlines, Air France, Delta Air Lines and Saudi Arabian Airlines. The carrier's Pearl Club members will continue to enjoy mileage accrual, redemption, and elite membership service benefits on the named 14 SkyTeam partner flights. The five airlines with which China Southern has not announced an ongoing cooperation are Aeroméxico, China Eastern Airlines, Garuda Indonesia, Kenya Airways, and TAROM.

On January 1, China Southern launched its own service brand known as "CZ Priority", which will replace the alliance's "SkyPriority" brand. This has been done to ensure that the carrier's gold and silver members and SkyTeam partners' Elite and Elite Plus members continue to enjoy the same benefits when flying on China Southern, including priority check-in, priority baggage, priority boarding, and VIP lounge access.

Commenting on the Chinese airline's departure, a SkyTeam spokesperson said: "SkyTeam and China Southern have worked very closely together over the last 12 months to ensure a smooth transition for all SkyTeam customers. This process was mostly completed on December 31, 2019. We continue to wish China Southern all the best in its future ambitions."

The Chinese carrier has been busy inking deals with airlines outside of the SkyTeam alliance over the last 12 months, including codeshares with American Airlines, British Airways, Finnair, Emirates, Qatar Airways, Qantas, and JAL - Japan Airlines. China Southern signed a frequent flyer cooperation with American in March 2019 and a joint venture agreement with British Airways in December 2019, with a frequent flyer cooperation to be launched in June 2020 with the UK airline.

According to the ch-aviation fleets module, China Southern operates an extensive fleet of 625 aircraft, including 163 B737-800s, 116 A320-200s and ninety-nine A321-200s. Its biggest base is at Guangzhou, where it offers nearly 485,000 weekly seats and over 2,500 weekly flights.