Key facts
- Gate reported 88.26% of total assets in cold storage and said the split could cover 104.58% of customer assets if hot wallets were drained.
- Coinbase said more than 99% of customer assets sit in offline cold storage and that it rebalances excess assets to cold storage.
- Upbit reported 99.17% of assets in cold wallets as of September 2026, above South Korea's 80% regulatory minimum, parent Dunamu said.
- OKX's security overview, last updated Sept. 18, 2026, said more than 95% of client crypto assets are held in cold wallets.
- Financial Supervisory Service figures put Bithumb at 94.76% and Coinone at 85% in cold wallets at the end of September.
Crypto exchanges disclosed how they divide assets between offline cold storage and internet-connected hot wallets in the week after an attack on Binance's hot-wallet infrastructure, according to a report published November 6, 2026.
Threat actors stole approximately $6.36 billion from Binance's hot wallets, most of it in about 20 minutes, according to blockchain analytics firm TRM Labs. Binance CEO Richard Teng said the vast majority of user assets are held in cold wallets, but the company has not provided a precise split.
Gate launched a Proof of Security framework on Thursday, reporting that 88.26% of its total assets were in cold storage and 11.74% in hot wallets. Gate said its cold storage could cover 104.58% of customer assets even if its hot wallets were completely drained, and that the data is still undergoing independent review by a third-party audit firm.
In a blog post Wednesday, Coinbase said more than 99% of customer assets are held in offline cold storage and that it continuously rebalances excess assets to cold storage. "Binance's reported hot wallet incident has understandably left customers asking how Coinbase protects customer assets from something similar happening here," the exchange said.
Upbit, described in the report as the largest cryptocurrency exchange in South Korea, confirmed on Tuesday that it holds 99.17% of its assets in cold wallets and 0.83% in hot wallets as of September 2026, figures already disclosed to the Financial Supervisory Service. A spokesperson for Upbit parent company Dunamu told Cointelegraph the ratio is the highest among South Korea's five major KRW-based exchanges and substantially above the regulatory minimum of 80%, adding that the company aims to keep hot wallet holdings below 1% of customer digital assets.
Financial Supervisory Service figures cited in earlier reporting put Bithumb at 94.76%, Coinone at 85%, Digital X, formerly Korbit, at 82.79%, and GOPAX at 80.54% at the end of September. OKX's existing security overview, last updated on Sept. 18, 2026, said it holds more than 95% of client crypto assets in cold wallets and less than 5% in hot wallets.
The report said the ratios are not necessarily directly comparable because exchanges use different reporting periods and may calculate cold-storage shares against different asset bases. It also said cold storage ratios offer only part of the picture of an exchange's security, since offline wallets can still be exposed through compromised signing systems, inadequate access controls or employees approving fraudulent transactions. Hong Kong's Securities and Futures Commission warned in an August 2025 circular that such weaknesses could compromise both hot- and cold-wallet infrastructure.