How long the line was on November 9, 2026
Explorer mempool.space counted 66,032 unconfirmed Bitcoin transactions at 05:45 UTC on November 9, 2026. Together they took up 34.8 million virtual bytes and offered 0.07243343 BTC in fees. The site’s own projection packs just under 1 million virtual bytes into each coming block, which made the backlog roughly 35 blocks deep.
Nobody was paying much to jump it. The “fastest” fee mempool.space recommended was 2 satoshis per virtual byte, and its projection placed about 30.8 million virtual bytes of the queue at rates between 0.1 and 0.124.
That floor is recent. Bitcoin Core cut its default minimum relay fee to 100 satoshis per 1,000 virtual bytes in version 29.1, published September 4, 2025, and version 30.0, published on October 10, 2025, carries the same 0.1 satoshi per virtual byte.
Every node keeps its own queue
Unconfirmed transactions “have no permanent status in Bitcoin,” the Bitcoin developer guide says, so Bitcoin Core keeps them in a memory pool. Its source code sets the defaults. A node’s pool may use up to 300 megabytes of memory, and a transaction expires after 336 hours, two weeks. Peers also purge some transactions to make room for others, so two explorers can show slightly different queues.
Ethereum has the same waiting room under another name. A submitted transaction is “added to a transaction pool consisting of all other pending network transactions,” according to ethereum.org, and a validator has to pick it for a block. The tip added to the base fee of an Ethereum gas fee exists to make that pick attractive, ethereum.org’s gas page says.
Waiting is not the same as paid
Suppose a buyer’s payment shows up in your wallet as pending. Is the money yours? Not yet.
Since Bitcoin Core 28.0, published October 2, 2024, full replace-by-fee has been the default policy. Under the project’s replacement rules, a new transaction that spends the same coins can replace one still waiting in the mempool if it pays a higher fee, and the original no longer needs to signal that it may be replaced.
The same rule rescues a stuck payment, since the sender can rebroadcast it with a higher fee. For anyone being paid, though, the better habit is the one exchanges use. Credit nothing until it has the deposit confirmations you require.