Crypto Exchanges Boost Cold Storage Disclosures Post-Binance Incident

In response to a significant hot wallet incident at Binance, major cryptocurrency exchanges including Coinbase, Gate, and Upbit are increasing transparency by disclosing the proportion of customer assets held in cold storage. This proactive measure aims to reassure users about fund security amid heightened industry-wide security awareness.

Last week, Binance reported a breach of its hot wallet infrastructure, with approximately $6.36 billion reportedly lost over a 20-minute period. In the aftermath, exchanges are sharing details about their asset allocation strategies.

Coinbase has stated that it keeps more than 99% of customer assets offline in cold storage. Gate reports 88.26% of its total assets are in cold storage, with 11.74% in hot wallets. Gate further claims its cold storage reserves could cover 104.58% of customer assets even if its hot wallets were fully drained. Upbit reported that as of September 2026, 99.17% of its assets are held in cold wallets, with the remaining 0.83% in hot wallets, figures reportedly disclosed to the Financial Supervisory Service.

Other exchanges have also provided cold storage figures. As of the end of September, Bithumb reported 94.76% in cold storage, Coinone 85%, Digital X (formerly Korbit) 82.79%, and GOPAX 80.54%. OKX stated that as of September 18, 2026, it holds more than 95% of client crypto assets in cold wallets and less than 5% in hot wallets.

These disclosures align with increasing regulatory attention on exchange security. South Korea, for example, has a regulatory minimum requiring exchanges to hold at least 80% of assets in cold storage, a threshold that Upbit’s reported ratio significantly exceeds. However, Hong Kong’s Securities and Futures Commission had previously warned in August 2025 about potential weaknesses that could compromise both hot and cold wallet infrastructure.

Despite these disclosures, direct comparisons between exchanges present challenges. The exact reporting periods and the specific asset bases used for calculating cold storage percentages are not uniform across all platforms. Furthermore, Gate’s Proof of Security (PoSEC) framework is still undergoing independent review by a third-party audit firm. Binance CEO Richard Teng has indicated that the “vast majority” of user assets are held in cold wallets, but the company has not provided a precise split.

Industry observers note that while cold storage is a critical security measure, it is not an infallible solution. Offline wallets can still be vulnerable through other means, and cold storage ratios alone do not provide a complete picture of an exchange’s overall security posture. The trend of increased transparency, however, is seen as a positive step in addressing user concerns following the recent incident.

Why This Matters

The materials describe a narrow update: Following a large-scale theft from Binance’s hot wallet, several cryptocurrency exchanges, including Coinbase, Gate, and Upbit, have publicly shared the percentage of customer assets they hold in cold storage (offline) versus hot wallets (online). Binance has not provided a precise split of user assets between cold and hot wallets.

Broader Context

Source materials place the factual news in this context: The article discusses the security practices of crypto exchanges in light of a recent attack on Binance.