What occur to fees paid if I don’t broadcast a transaction immediately ?

[unknowncustomer]

Hello,
Let’s say I choose to spend an UTXO with Sparrow, set up the fees (let’s say 10 sats/vb), sign offline the transaction but don’t broadcast it immediately.
And imagine that I broadcast the transaction on the internet only 1 year later, when fees are 100 sats/vb.
What happened then ??
Will the fees be adjusted automatically in order to process my transaction ?
Or will I keep 10 sats/vb ?
Or will my transaction never arrive ?

[1714583036]

1714583036

[1714583036]

1714583036

[1714583036]

1714583036

[1714583036]

1714583036

[Charles-Tim]

If nodes are accepting 10 sat/vbytes, it will be broadcasted. But if mempool priority fee is over 100 sat/vbytes, nodes may not accept such low transactions until you increase the fee by making another transaction.

[hosseinimr93]

Your transaction will be broadcasted with the fee rate of 10 sat/vbyte.
Take note that with any change in transaction data, the signature becomes invalid and the transaction needs to be signed again. So, if you want to broadcast your transaction with a different fee rate, you should make a new transaction and sign it again.

[ranochigo]

Your signed transactions would be immutable unless you modify the transaction and sign the new transaction. Your fees will remain the same, and it would be as if you've just made a transaction that pays 10sat/vb in fees.

That is contingent on the fact that you have never spent the UTXO in another transaction and are still valid.

[Knight Hider]

Sign a new transaction with higher fee, or CPFP (Child pays for parent) to the rescue from the receiving wallet.

--Knight Hider

[Charles-Tim]

Sign a new transaction with higher fee, or CPFP (Child pays for parent) to the rescue from the receiving wallet.

When Ordinals NTFs and BRC-20 tokens were created, the transaction fee rate increased to over 300 to 500 sat/vbyte. I saw purging around that time to be over 32 sat/vbyte. That means transactions that pay lower than that would have been dropped from mempool and replaced by higher fee transactions. Making a transaction using a fee rate lower than 32 sat/byte at the time too will be rejected by nodes.

In case such transaction was broadcasted and not rejected but the fee is not enough.
If RBF is enabled, which is enabled by default on what that supports it, RBF can just be used to pump the fee instead of CPFP to take advantage of lower fee.

[FatFork]

OP, your question is pretty much answered, so you might want to think about locking this topic.

Just to emphasize what others have already said, it doesn't matter when the transaction is broadcasted to the network; once a transaction is signed, it becomes immutable, including the transaction fee. If you want to change the fee amount or any other data, you'll need to replace the original transaction with a new one.