Bitcoin Forum

I've just seen the below tx go through with a 191 sat fee. I don't remember seeing such a low fee in a confirmed transaction lately.
  https://mempool.space/tx/507402f95a07511bb8ba3d5fecfa65bb1d9e44367aef42d38cfa8238c243f54b

Anyone aware of lower fee examples (in 2022)?

EDIT: I assume fees can be even lower with segwit, right?

The lowest fee rate you can set for your transaction is 1 sat/vbyte. That's the current minimum relay fee rate and any transaction with lower fee rate would be rejected by the nodes.
If your transaction is segwit and it includes 1 input and 1 output, its size would be around 110 vbyte. So, the lowest possible fee is around 110 satoshi.

The lowest I've seen was 0. But that was many years ago.

As said, in 2022 the lowest fee you can set is 1 sat/vByte. And as you can see we discuss about fee per vByte, not per total.
So the total fee depends on addresses used and the size (in vBytes) of the transaction.

If you want to have very low fee you have to:
* use pure segwit address for both input and output
* use only one input
* have only one output (i.e. no change, i.e. entirely spend the input for the output + tx fee)

As you can see, this kind of transactions don't really have many use cases (apart of sending to self and maybe donations).

Technically lowest fee is zero.
Practically it is 1 satoshi/vbyte so the total depends on the tx virtual size.

Since that total fee depends on the transaction size theoretically the lowest fee should be around 60 satoshis since that is the smallest transaction possible which would be non-standard. A transaction that has no signature (empty script) and no locking script (empty).

version(4)+inputcount(1)+outpoint(32+4)+sequence(4)+script(1)+outputcount(1)+amount(8)+script(1)+locktime(4)=60 bytes => 60 satoshi.

The lowest possible value is 0, but there are very few nodes that will relay such transaction. You can communicate with a mining pool, though, and have it included into their mempool.

Correct me if I'm wrong but the lowest fee a standard transaction can have is one that spends one SegWit input and creates one SegWit output. I've done it quite frequently, and paid 121 sats.

Here is a transaction with fee exactly 1 sat from September 2022
https://mempool.space/tx/5d1c002042d56dd856870de97349b5995cd258d42be0c0a3a104ed8f2be047c0

As far as I know, the size of a transaction with 1 native segwit input and 1 native segwit output should be around 110 vbyte.
Assuming the fee rate used for such a transaction is 1 sat/vbyte, the total fee should be 110 satoshi.

Click here (https://blockchair.com/bitcoin/transaction/2ae360bf00991223ff55ee8afaf05ac489a96eeb5581f9c9221838c5d063d0e0) to see a transaction paying 110 satoshi as fee.

Or if you have your own mining pool, no more headaches and you can have it completely free:
https://mempool.space/tx/5a19c18e1cf2fc57626a6814854c3315d9d072aeabfa287afc6cdfc987e127b8

F2pool consolidating in one of its owned mined blocks.


Nothing new, it has been going like this for months:
https://bitcointalk.org/index.php?topic=2848987.msg60272306#msg60272306

Great informative responses, thanks everyone  ;D

Most clients will only allow users to set a fee rate when crafting a transaction, however, it is possible to craft a transaction with a 'flat' fee, for example, x sats. Or in the case of what j2002ba2 found (https://bitcointalk.org/index.php?topic=5417659.msg61149340#msg61149340), 1 sat.

Regardless of what nodes will relay, as long as the transaction is valid, if a pool is willing to include said transaction in its found block, it has the potential to be confirmed, if the pool is aware of the transaction. Most of the time, this will involve either the pool receiving compensation for including said transaction(s) off-chain, or the pool including its own transaction(s) in its found blocks.

You are correct and since OP didn't ask more clearly, it is a very good answer.
However, unless one has his own pool, this doesn't worth the hassle, so it has only an "academic value". Still, nice catch!

I think pools will eventually start selling their block space (off chain) to large consumers of blocks space (for example to exchanges) via long term deals. Today, pools sell their block space (off chain) to retail consumers, often at a huge markup, however the required tx fee is currently so low, that most likely, few need to do this.

This makes no financial sense at all. For both the mining pool and the buyers.
If the pool is selling the space at a higher price that means the buyer is basically paying a higher fee. In other words they could just pay a higher on-chain fee in first place. If they are selling it at a lower price that means they are losing revenue which again makes no sense.
There is no shortage of demand for the block space either for the pools to need to do some marketing and ensure their revenue.

The sale of block space at a premium to 'retail' customers when fees are high makes sense because many lack the technical skills to double-spend a transaction to increase the fee. The high fee is really more for technical help than for including the tx in a block.

Pools could sell block space well into the future to companies who expect to need a lot of block space in the future. This will allow both the pool and the consumer of block space to have a more predictable revenue and expenses. Today, transaction fees to get transactions confirmed, even on a next-block basis is very close to zero, but this will not always be the case.

There are 18,161 transactions which have paid a fee of exactly 1 sat: https://blockchair.com/bitcoin/transactions?q=fee(1) (https://blockchair.com/bitcoin/transactions?q=fee(1))

This could be a risk to the mining pool: when they sell block space above market value, more miners will join their pool. But when fees go up and their long-term contract forces them to sell transactions under market value, miners will move to other pools.

This will not be an issue if the pool has control over the miners (in exchange for the guarantee of more steady tx fee revenue). The point of entering into these types of arrangements is to ensure that costs/revenue are predictable over long periods of time. The "pool" could sell something similar to what we know today as a 'cloud mining contract', or the pool could own the hardware for its own account, or was in some other situation in which, this type of arbitrage would not be possible.