As newly redeveloped office buildings in Seoul’s Central Business District (CBD) begin full-scale marketing efforts to attract tenants, competition within the CBD is heating up.

According to the commercial real estate leasing industry on May 20, several upcoming developments—including G1 Seoul in Gongpyeong Districts 15 and 16, and projects in Euljiro 3-ga Districts 6 and 12—are now actively promoting leasing through major advisory firms such as CBRE Korea and GenstarMate.

Additionally, two large-scale redevelopment projects in the Sewoon District—Block 6-3-3, scheduled for completion in 2028, and Blocks 3-2 and 3, set for 2029—have already begun early efforts to attract tenants.

Together, these five buildings will offer over 495,000 square meters of total floor area, potentially triggering a wave of tenant relocations and reshaping the office leasing landscape in the area.

G1 Seoul, located in Gongpyeong Districts 15 and 16 and scheduled for completion in April 2025, will feature two office towers—Tower A with 25 floors above ground and 8 underground, and Tower B with 12 floors above ground and 8 underground. The total floor area is 143,431 square meters.

Ranspert AMC, the developer behind the project, is pushing for a pre-sale of G1 Seoul and is therefore prioritizing tenant acquisition to maximize the building’s sale price. According to industry sources, leasing is currently being promoted at an effective net operating cost (E. NOC) of approximately 115.0 USD per square meter

It has been reported that Kumho Petrochemical, which currently occupies Signature Tower as its headquarters, has submitted a Letter of Intent (LOI) to lease space at G1 Seoul. However, some speculate this may be a negotiation tactic ahead of the company’s lease renewal in 2028, making it uncertain whether they will ultimately relocate.

Following G1 Seoul, another major development—Euljiro 3-ga District 6, set to be completed in May 2025—is also actively seeking tenants. This building will feature 17 floors above ground and 6 underground, totaling 60,392 square meters. The Korea Scientists and Engineers Mutual-aid Association (SEMA) had initially targeted the site for its new headquarters and pursued a pre-sale deal but later withdrew and instead won priority negotiation rights for NC Tower 1 in Samsung-dong, Gangnam District in February.

Meanwhile, the I-eul Tower, located nearby in Euljiro 3-ga District 12 and slated for completion in November 2025, has joined the tenant race. The building will offer 44,906 square meters across 17 floors above ground and 8 underground. Kyobo AIM Asset Management, which acquired the site in 2023, is marketing I-eul Tower as a “five-star office” equipped with premium amenities rivaling luxury hotels. To that end, the firm has signed a design contract with Jongkim Design Studio, known for its work on high-end residential and hospitality projects like Fozes Hangang in Gwangjin-gu, Seoul, and Osiria Busan Penthouse in Gijang-gun, Busan.

An industry insider commented, “With over 2.48 million square meters of new office space expected to be supplied in the CBD by 2030, competition to secure tenants first will only grow more intense.”