Ethereum and Bitcoin are showing opposing short-term exchange-flow patterns as crypto holders reassess custody. ETH balances on centralized exchanges have fallen to roughly 15.12 million, from about 16.86 million earlier this year, representing a year-to-date reduction of approximately 1.74 million ETH, or around 10%. The decline has continued through 2026, leaving reserves at levels not seen since 2015. More than 34% of Ethereum’s total supply is now committed to staking (locking crypto to help secure the network and earn rewards), while other holdings appear to be moving into self-custody wallets. Bitcoin exchange reserves have also followed a longer-term downward trend, reaching 6.6% of circulating supply in July 2026, according to Santiment data. However, about 28,000 BTC flowed back onto tracked exchanges in less than three weeks, including a 16,349 BTC increase in user holdings at Binance, based on the exchange’s latest Proof of Reserves update. Analysts caution that falling exchange balances do not automatically produce higher prices because ETF flows, macroeconomic conditions and regulatory developments also affect supply and demand. Spot Bitcoin and Ethereum ETFs have created new channels for institutional buying and redemptions that may influence prices without appearing in traditional exchange-balance data. BTC and ETH supply metrics have reached lows not recorded since 2017 and 2015, respectively, while Ethereum’s staking yields and self-custody momentum appear to be supporting a more durable flow away from exchanges.