Crypto trades 24/7, but Bitcoin follows New York hours

Researchers analyzed 87,672 hourly observations from Kraken’s XBT/USD market covering 2016–2025 and measured where and when Bitcoin’s price moves concentrated within each day.

The study reports that the nine-hour window from 13:00 to 21:59 UTC made up 50.6% of Bitcoin’s daily realized variance in 2022–2025. That window is 37.5% of a 24-hour day, which the researchers present as a marked concentration of price discovery during those hours.

Tests using US daylight-saving transitions showed the hour of peak volatility moved with New York clock changes. During 2022–2025 the most volatile hour shifted from 14:00 UTC in US daylight-saving time to 15:00 UTC in standard time. The study also compared matched trading days with weekday US market holidays and found Bitcoin’s share of variance during US hours fell by 13.9 percentage points on holidays, from 55.7% to about 41.9%.

No comparable clock-synced pattern appeared in 2016–2018. A window-free measure placed Bitcoin’s variance-weighted center at 14.1 UTC in 2016–2018 and at 17.1 UTC in 2022–2025. The paper reports the concentration index increased by more than 40% over that span.

A change-point analysis identified November 2021 as the main structural break in the trend toward greater US-hours volatility. The analysis did not find a distinct break tied to the December 2017 introduction of CME Bitcoin futures or to the January 2024 approval of US spot Bitcoin ETFs. The authors show that broad before-and-after comparisons can make long-running trends look like sudden changes, while symmetric one-year windows around events reduce apparent effects.

The pattern extends beyond Bitcoin. Six of seven other long-listed assets on Kraken showed rising US-hours shares between their early and recent two-year samples, including Ethereum, XRP, Solana, Cardano, Dogecoin and Chainlink. XRP’s US-hours share rose from 37.2% to 46.2% and Ethereum’s from 41.8% to 48.2%. Litecoin did not show a statistically significant trend.

Weekend activity has weakened relative to weekdays. Bitcoin’s weekend-to-weekday volatility ratio fell from 0.96 in 2016 to 0.60 in 2024 and 0.64 in 2025. Weekend trading volume as a share of weekday volume dropped from 0.78 to about 0.43 in 2024 and edged to 0.46 in 2025.

The paper notes practical implications for trading and risk management. Models that assume volatility is evenly spread across the day can understate exposure during US hours and overstate overnight risk. Lower weekend liquidity may complicate hedging between spot markets that trade continuously and derivatives tied to traditional market hours.

Limitations are also noted. The analysis is based primarily on a single exchange and ends with data through 2025. The authors recommend multi-venue confirmation and order-book or trade-level data to determine how much of the timing effect comes from ETF creation and redemption flows, futures positioning, market-maker hedging or other institutional activity.