The average age of existing condominiums sold in the Greater Tokyo Area (GTA) reached 24.53 years in 2024, increasing by 0.70 years from 2023, according to a report released on February 25th by the East Japan Real Estate Information Network.
Newly listed GTA existing properties (both condos and single-family homes) averaged 30.22 (+0.81%) years, surpassing the 30-year mark for the first time ever.

Graph courtesy of East Japan Real Estate Information Network, translated by Patience Realty.
Percentages listed below are year-on-year comparisons; in other words, the percentage changes from 2023 to 2024.
The gap between the ages of sold and newly listed properties expanded to 5.69 years (+0.11 years).
The age gap between sold and listed properties widened to 2.68 years (+0.42 years).

Graph courtesy of East Japan Real Estate Information Network, translated by Patience Realty.
Newly built inventory has been decreasing for years, forcing more buyers into the existing property market. While the gap between sold and listed (on-market) average property age is widening, both are rising in age forcing buyers to buy older than before.
Further reading:
GTA 2024 Existing Property Market Building Age Report (Japanese only)
Source:
R.E. Port News (Japanese only)