Dr -ck (@ckpooldev) reported that block 910440 was the first solo.ckpool block to include transactions paying below 1 sat/vB.
Sub 1sat/vB transaction discussion and reversal of decision to mine them on solo ckpool.
Block 910440 https://t.co/6WKLc4J07u is the first block that solo ckpool has mined that has included sub 1sat/vB transactions. I made this change because the bulk of the mining pools are now… https://t.co/JsV4yJxaV7
— Dr -ck (@ckpooldev) August 18, 2025
The change was made because many mining pools had already begun including such transactions, and aligning with this approach reduced delays in building new blocks.
After the block was mined, Dr -ck examined the results. Out of roughly 4,900 transactions, about 3,300 were below 1 sat/vB.
The additional reward generated from these transactions was approximately 0.0018 Bitcoin (around $220), representing about 0.06% of the 3.125 Bitcoin subsidy.
According to Dr -ck, these low-fee transactions tended to be small and often created one or two new UTXOs.
Following the review, Dr -ck announced that solo.ckpool will continue to accept and relay sub-1 sat/vB transactions into the mempool but will no longer mine them.
He explained that, in his assessment, such transactions will not provide a meaningful increase in mining rewards unless the block subsidy drops below 0.2 Bitcoin.
“The block reward needs to have dropped substantially for such low fee transactions to add meaningful reward to mining pools, and I would only consider doing so if the reward was at least 1% more.”
Dr -ck also encouraged other pool operators to review the data themselves before adopting or rejecting these transactions:
“Some changes in behaviour appear to be done on whim and feeling, and that's simply not enough when we have a plethora of hard data at our disposal.”
Community responses varied. Philip D’Ath thanked Dr -ck for carrying out the analysis, while EaSt SiDe questioned whether excluding low-fee transactions leaves potential revenue behind.
Dr -ck responded that enabling such transactions might reduce overall fee levels in the long term:
“It allows everyone to lower their fees, so what might look like $200 more now may in fact be $2000 less in future.”