Seoul CBD Vacancy Hits Decade High

Prime office vacancy in Seoul's central business district has climbed to its highest level in ten years, reaching approximately 10% as a wave of new supply enters the market and major tenants relocate to newer developments in competing submarkets. The sharp uptick marks a significant reversal from the tight conditions that characterised Seoul's Grade A office sector between 2020 and 2024, when vacancy rates hovered between 2% and 5% across the CBD. Landlords in older buildings are now facing mounting pressure to offer concessions, rent-free periods, and fit-out contributions to retain and attract occupiers. The trend has raised concerns among institutional investors holding legacy assets in the traditional Gwanghwamun and City Hall corridors.

  • CBD vacancy rate: ~10% (Q1 2026)
  • Previous cycle low: 2.3% (Q3 2022)
  • New supply pipeline (2026–2028): ~1.2 million sqm across Seoul metro
  • Average Grade A rent (CBD): KRW 105,000/pyeong/month
  • YoY rent change: -3.2%

Market Context

The vacancy spike is driven by two converging forces. First, Seoul's development pipeline has accelerated sharply, with several large-scale projects in the Gangnam Business District and Yeouido completing or nearing handover. Buildings such as the redeveloped Parc1 Tower and newer Gangnam Station-area developments have drawn anchor tenants away from ageing CBD stock, offering modern specifications, better ESG credentials, and superior floor-plate efficiency. Second, several major financial institutions and technology firms have consolidated operations into single-campus headquarters outside the traditional CBD, leaving behind fragmented space that is proving difficult to backfill.

Comparable dynamics have played out in other Asia-Pacific office markets. Hong Kong's Central district saw vacancy rise above 11% in late 2024 as occupiers decentralised to Kowloon East, while Singapore's Raffles Place recorded a more modest uptick to around 5.5% amid controlled supply. Seoul's situation is notable because the CBD had been one of the region's tightest markets for the better part of five years, and the speed of the correction has caught some asset owners off guard. Analysts at Cushman and Wakefield have noted that the CBD's older building stock, much of it dating from the 1990s and early 2000s, faces a structural competitiveness gap against newer towers that meet the sustainability and wellness standards increasingly demanded by multinational occupiers.

Rental Pressure Building

Effective rents in Seoul's CBD have already started to soften. Headline asking rents have declined by approximately 3.2% year-on-year, but the real erosion is steeper once incentive packages are factored in. Market sources indicate that landlords of secondary Grade A buildings are now offering rent-free periods of up to six months on new five-year leases, compared with two to three months a year ago. Net effective rents in these buildings may have fallen by as much as 8% to 10% on a like-for-like basis. Prime buildings with recent refurbishments have fared better, maintaining occupancy above 90%, but even trophy assets are not immune to the broader decompression.

What This Means for Investors

For investors with exposure to Seoul CBD office assets, the near-term outlook calls for caution. Cap rate expansion is likely as net operating income compresses, and assets requiring significant capital expenditure to compete with new-generation buildings could see valuations adjust by 10% to 15% from peak levels. Conversely, the dislocation may create acquisition opportunities for well-capitalised buyers willing to reposition older stock through refurbishment or conversion to mixed-use. The Korean government's ongoing relaxation of zoning rules in parts of the CBD to permit residential and hotel conversion adds a potential upside path for select properties. Investors should monitor leasing velocity through the second half of 2026, as a sustained period above 8% vacancy would signal a more prolonged correction rather than a temporary supply-driven blip.