[Sep 2025]Mempool empty, Consolidate your small inputs @0.22 sat/vbyte

[LoyceV]

According to mempool.space, there are now many blocks to be filled with 0.27 sat/vbyte transactions. So if you're looking for a cheap consolidation this weekend, 0.28 sat/vbyte is your best bet.

[LoyceV]

Mempool.space is the best source for low-fee estimates. The next block is expected to be 60% filled with 0.24 sat/vbyte transactions. That means 0.25 sat/vbyte could be enough to get confirmed in the next block (depending on which miner finds it, and of course how long that takes).

Don't go too low, my 0.21 sat/vbyte test-transaction (created September 14) is still unconfirmed.
Note that Electrum's estimate of how far the transaction is from the tip is far off for low-fee transactions.

[philipma1957]

Mempool.space is the best source for low-fee estimates. The next block is expected to be 60% filled with 0.24 sat/vbyte transactions. That means 0.25 sat/vbyte could be enough to get confirmed in the next block (depending on which miner finds it, and of course how long that takes).

Don't go too low, my 0.21 sat/vbyte test-transaction (created September 14) is still unconfirmed.
Note that Electrum's estimate of how far the transaction is from the tip is far off for low-fee transactions.

Has any one got a trezor to send under 1 sat.

Last time I tried it was a no go.

[LoyceV]

Has any one got a trezor to send under 1 sat.

It should work if you connect your Trezor to Electrum and connect to for instance electrum.loyce.club:50002 after you enter this in console:

Code:

wallet.relayfee = (lambda: 0)

Full explanation: LoyceV's 0.1 sat/vbyte Electrum Server Adventure.

[TryNinja]

Has any one got a trezor to send under 1 sat.

It should work if you connect your Trezor to Electrum and connect to for instance electrum.loyce.club:50002 after you enter this in console:

Code:

wallet.relayfee = (lambda: 0)

Full explanation: LoyceV's 0.1 sat/vbyte Electrum Server Adventure.

Btw, I was under the impression that you didn't need to send this command on Electrum's latest versions anymore, no? It might be my brain lying to me, but I think I already tried that a few weeks ago and managed to sign the tx normally (then push it through mempool.space).

[philipma1957]

Yeah I tried trezor today doing 0.9 sat.

Zero issues to do it.


So seems they did an upgrade.

I will try 0.8 sat next sent i do.

[LoyceV]

Btw, I was under the impression that you didn't need to send this command on Electrum's latest versions anymore, no?

I tried, and it doesn't work:

This transaction requires a higher fee, or it will not be propagated by your current server. Try to raise your transaction fee, or use a server with a lower relay fee.

(this was while connected to my own Electrum server)

It might be my brain lying to me, but I think I already tried that a few weeks ago and managed to sign the tx normally (then push it through mempool.space).

Aren't you using your Relay Fee Zero Plugin for this?

[TryNinja]

Btw, I was under the impression that you didn't need to send this command on Electrum's latest versions anymore, no?

I tried, and it doesn't work:

This transaction requires a higher fee, or it will not be propagated by your current server. Try to raise your transaction fee, or use a server with a lower relay fee.

(this was while connected to my own Electrum server)

Aren't you using your Relay Fee Zero Plugin for this?

Hmm... you are right.

When the the latest version was released, I tried disabling my plugin and the tx still went through. I had the impression that Electrum fully reloaded itself after I disabled the plugin (the window flashed), but it turns out that the initial command persisted in the QT, which is why I got it to work "without the plugin".

Also, the change logs gave me this impression:

# Release 4.6.2 (Aug 25, 2025)
 * General:
   - changed: minrelayfee clamps from [1, 50] to [0.1, 50] sat/vbyte (#10096)

[joker_josue]

It might be my brain lying to me, but I think I already tried that a few weeks ago and managed to sign the tx normally (then push it through mempool.space).

Aren't you using your Relay Fee Zero Plugin for this?

Since I started using LoyceV server I have been able to send transactions below 1sat/vbyte. At least I've already made one like that!

I'm not using any plugins. I'm on portable version 4.6.2.

[philipma1957]

My trezor simply allowed 0.9 sats per byte.

I was impressed

This scales interestly

The total k fee was about 25 us cents i sent the coin from a legacy address

So if btc was 1,250,000 total fee would be $2.50

This would allow for

1.56 in 2028
0.78 in 2032
0.39 in 2036 a block would be worth about 400k which is about the price of a block now so we could easily scale to that which is 11 years from now.

I AM ENCOURAGED BY THIS.

[LoyceV]

My trezor simply allowed 0.9 sats per byte.

That means you overpaid
Look at mempool.space, and hover your mouse over the "Mempool Googles" on the left: 0.31 sat/vbyte is enough to get in the next block. Unless the miner rejects transactions paying less than 1 sat/vbyte, but in that case 0.9 sat/vbyte wouldn't have gotten your transactin in anyway. So when paying less than 1 sat/vbyte, don't pay too much

[LoyceV]

By the way: you got 40 sats, where you wanted, good luck sweeping them: https://mempool.space/address/bc1qzeflmklr2l4kdjkx4ak027jcg8jcs3hfne4fqy

For the reader who doesn't know what this is about: How to send 0.0000004 BTC?
Sweeping them isn't difficult: this transaction includes another (dust) input, sends 38 out of 40 sats as a miner fee, and is waiting for 0.21 sat/vbyte transactions to be mined.

After exactly 4 weeks, my 0.21 sat/vbyte transaction is now confirmed!
Judging by mempool.space, I'd say 0.22 sat/vbyte is currently the optimal fee with a decent chance of getting confirmed today.

[philipma1957]

My trezor simply allowed 0.9 sats per byte.

That means you overpaid
Look at mempool.space, and hover your mouse over the "Mempool Googles" on the left: 0.31 sat/vbyte is enough to get in the next block. Unless the miner rejects transactions paying less than 1 sat/vbyte, but in that case 0.9 sat/vbyte wouldn't have gotten your transactin in anyway. So when paying less than 1 sat/vbyte, don't pay too much

just testing downwards

.9 passed
.8 is next

i almost never spend btc it will take time to scale down to

.1 sats

[LoyceV]

just testing downwards

.9 passed
.8 is next

I'll help you, someone tested 0.22 already an hour ago. It confirmed in 2 minutes.

i almost never spend btc it will take time to scale down to

Your test is flawed: the lowest possible fee depends on the rest of the network. If 0.22 is enough, paying 0.8 makes no sense. But if the minimum is higher, 0.8 doesn't make sense either. Fees are dynamic.

[philipma1957]

just testing downwards

.9 passed
.8 is next

I'll help you, someone tested 0.22 already an hour ago. It confirmed in 2 minutes.

i almost never spend btc it will take time to scale down to

Your test is flawed: the lowest possible fee depends on the rest of the network. If 0.22 is enough, paying 0.8 makes no sense. But if the minimum is higher, 0.8 doesn't make sense either. Fees are dynamic.

my test is not flawed in the least.

today I did 0.8 sats and it worked.
on my trezor easy peasy

https://btc1.trezor.io/tx/d5673baed165acdfd40141221660b5345d6fe8aa632f020bda6ecbe6686dfde1

this was 0.9 sats
https://btc1.trezor.io/tx/c5380d18e25bcd914a8b4e696d1da27d39ad3272cdd5bc842dd7ba5d63c824a7


I do not care about over paying a few pennies in fees.

I care about showing my trezor will allow

0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1

sat sends with confirmation.

so far I have physically shown

0.9
0.8

are easy to do and worked.

all I want is a list of tx done on my trezor showing confirms at

0.9 btw they rounded to 0.91
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1


then anyone can see the list and complain to anyone refusing to allow the send or accept the send.

these are reference documents for the community

they are slow as I do not move btc very often