The article "The Bitcoin Lightning Network Summary" by lightning.network mentions:

"Lightning enables one to send funds down to 0.00000001 bitcoin without custodial risk. The bitcoin blockchain currently enforces a minimum output size many hundreds of times higher(1), and a fixed per-transaction fee(2) which makes micropayments impractical. Lightning allows minimal payments denominated in bitcoin, using actual bitcoin transactions."

(1) Is there in (standard) Bitcoin a limitation for minimum amount of payment (output size)?

(2) Is there a fixed per-transaction fee for payments in Bitcoin? And if yes, how much is this fee amount?


Consider the following answers for consensus (chain validation) and node-policy (mempool acceptance, tx propagation).


  • (1) Zero Satoshis.
  • (2) No.

Node policy:

  • (1) See 2
  • (2) Nodes generally have a minimum-fee policy for mempool acceptance. Therefore, the total output amounts of a transaction cannot be zero, though individual output amounts can. See OPRETURN outputs for example.

Payments in lightning are denominated in mSat's, though the balance is rounded to Sat's can be delivered during channel closing.

  • Thank you, but really I did not get my answer. In LN doc, it's mentioned "bitcoin enforces a minimum output size, many hundreds of times higher than 1 Satoshi" that means minimum output size in bitcoin is very higher than LN (while this value in LN is 1 Satoshi, in Bitcoin is hundreds times higher). You may mean total amount of all outputs of a tx cannot be zero; And if so, what is value of this non-zero limitation?
    – Questioner
    Jan 16 '19 at 14:09
  • In second question, in LN doc, it's mentioned "fixed per-transaction fee makes micropayments impractical." You may mean this fixed fee is determined by miners; however, in that case the fees cannot be a fixed value. Can you explain in more detail? Thank you
    – Questioner
    Jan 16 '19 at 14:11
  • 1
    @sas I think the paper is confusing, there is a minimum total output which depends on the node-policy's minimum fee rate (for DoS prevention), but for individual outputs you can definitely do a zero output. Lightning in fact allows for millisatoshi transactions, see github.com/lightningnetwork/lnd/blob/master/lnwire/…
    – JBaczuk
    Jan 16 '19 at 15:33
  • @JBaczuk Agree. There are some factual errors in the paper, without having read it in its entirety.
    – James C.
    Jan 16 '19 at 15:35
  • @JBaczuk , I think so too, however, this article is published in official Lightning Network website: lightning.network/docs (Lightning Network Summary)
    – Questioner
    Jan 16 '19 at 15:39

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.