Bitcoin changed hands at $66,597 at 8:30 a.m. Eastern on Tuesday, March 31, 2026, alongside a $1.33 trillion market cap and $48.8 billion in 24-hour volume. The price stayed inside a $66,037–$68,130 intraday band, with technical signals leaning neutral-to-bearish as it remained below key moving averages.

Bitcoin security researcher Justin Drake said on March 31 that two new quantum-computing papers increased his estimate of a "Q-day" to a 10% chance by 2032, a point when widely used cryptography could be broken. He argued the work reduces the resources needed for attacks based on Shor's algorithm and could, in best cases, shrink key-cracking time to minutes, though the threat remains theoretical for now.

Bhutan's Royal Government has moved roughly 375 Bitcoin, valued at about $25.19 million, in a transaction recorded on March 31. The BTC was sent to an intermediary wallet that has previously been associated with outflows toward Galaxy Digital. The transfer follows a series of sizable March movements that have lifted 2026 outflows above $152 million.

Bitcoin traded around $65,200–$66,689 as roughly 9 million BTC—about 45–46% of circulating supply—sat at an unrealized loss, with short-term holders showing $113.9 billion in losses. Analysts say similar readings in mid-2018, mid-2022 and January 2023 were followed by either deeper drawdowns or extended consolidation, leaving $63,000 and $69,000 as key nearby levels.

Bitcoin (BTC) moved back below $66,000 on Tuesday after briefly pushing above $68,000, a move some analysts described as a bull trap. Spot-market CVD commentary suggested late buyers were quickly underwater, while a negative Coinbase Premium was cited as another warning sign. The pullback came ahead of an 8 a.m. Eastern press briefing by US Secretary of War Pete Hegseth, with WTI crude having traded above $106 earlier in the week.

Joao Wedson, founder of crypto analytics platform Alphractal, highlighted $60,490 as a pivotal Bitcoin level tied to Binance’s reserve realized price. He said staying above it keeps the exchange’s BTC holdings in profit, while a sustained move below would place that reserve in unrealized loss and could intensify bearish conditions. Wedson also warned that a break may weaken sentiment and reinforce a sell-pressure feedback loop.

Nakamoto Inc., a Nasdaq-listed bitcoin treasury company trading as NAKA, reported selling 284 BTC in March 2026 for about $20 million to fund operating needs tied to recent acquisitions and near-term liquidity. The firm’s Form 10-K for the year ended Dec. 31, 2025 listed a weighted-average acquisition cost of about $118,171 per BTC, implying an estimated ~40% realized loss on the sale. After the transaction, Nakamoto said it still holds roughly 5,058 BTC in treasury.

Google’s Quantum AI team said in a Tuesday whitepaper and blog post that Bitcoin and Ethereum cryptography tied to ECDLP-256 could be broken with fewer than 500,000 physical qubits and about 1,200 logical qubits. The paper also models a live Bitcoin attack that could steal coins mid-transaction in around 9 minutes, implying a 41% chance of beating Bitcoin’s 10-minute block time.