Lucky solo Bitcoin miner beats the odds to win $350,000 block reward

A solo Bitcoin miner beat substantial odds to solve a block and take home the full subsidy and transaction fee reward late Thursday.

The miner collected a total of 3.173 $BTC ($348,948) for mining block 903,883, using solo Bitcoin-mining software from CKpool, according to the Bitcoin explorer Mempool. This comprised 3.125 $BTC in block subsidy rewards ($343,709) and 0.048 $BTC ($5,239) in transaction fees.

"Congratulations to miner bc1q~9sj3 with 2.3PH for solving block number 301 on the EU solo.ckpool.org!" CKpool developer Con Kolivas posted on X. "A miner of this size has about a 1 in 2,800 chance of solving a block every day, or once every 8 years on average."

The solo miner's hashpower is the equivalent of 0.00026% of the Bitcoin network's total estimated hashrate of 874 EH/s (874,000 PH/s) on July 3, per Mempool's data. Leading public Bitcoin miner, MARA, has a hashrate of approximately 57.3 EH/s, according to its latest disclosure. Bitcoin's hashrate measures the total computational power dedicated to the network by miners.

Smaller Bitcoin miners usually join shared pools to earn steady, proportional rewards since solo mining has an extremely low chance of winning a block. Nevertheless, some individuals attempt solo pools in the hope of securing the full block reward, thereby avoiding fees and potentially winning a substantial, lottery-like prize despite the odds.

However, as Kolivas points out, it's not the first time a solo miner has picked up the entirety of the block rewards, nor one of the luckiest. For example, a solo Bitcoin miner with a hashrate of just 126 TH/s beat odds of 1 in 1.3 million to mine a block in 2022 — picking up around $260,000 in rewards at the time.

Most recently, a solo miner with a weekly hashrate of 6.1 PH/s earned $327,625 on June 5. The caveat then was that the miner temporarily increased their compute power as high as 261 PH/s to mine the Bitcoin block — suggesting they likely rented additional hashrate to better their odds of earning the block reward. Still, it remains a relatively rare event.

There was no sign of rented hashpower this time around, though, in Kolivas' view. "They'd been mining consistently with 2.3PH for quite a while, so I doubt it, but anything's possible," he said, responding to a query if the miner was using hashrate bought from NiceHash again.

However, that doesn't mean the solo miner is a very small or cheap operation either, with their 2.3 PH/s equivalent to around 11 Antminer S21s, with a retail value of $3,780 per unit, according to manufacturer Bitmain.