<p>In your c-lightning node you have configured your <code>maximum fee rate</code> which is used by the <code>pay</code> command to do the payment. </p>

<p>The <a href="https://github.com/lightningnetwork/lightning-rfc/blob/master/04-onion-routing.md#failure-messages" rel="nofollow noreferrer">BOLT04</a> describes how overpaying up to twice the amount to obfuscate payments in order to have better privacy is part of the protocol: </p>

<blockquote>
  <p>if the amount paid is more than twice the amount expected:
  SHOULD fail the HTLC.</p>
  
  <p>SHOULD return an incorrect_or_unknown_payment_details error.</p>
  
  <p>Note: this allows the origin node to reduce information leakage by altering the amount while not allowing for accidental gross overpayment.</p>
</blockquote>

<p>In combination with <a href="https://github.com/ElementsProject/lightning/pull/1257" rel="nofollow noreferrer">this merged pull request</a> c-lightning fixed <a href="https://github.com/ElementsProject/lightning/issues/1089" rel="nofollow noreferrer">this issue</a>
implementing random overpayments up to the maximum fee rate. </p>

<p>So generally c-lightning will randomly overpay your transaction with an amount that is lower to the maximum feerate you are willing to pay. </p>

<p>Not that <a href="https://github.com/lightningnetwork/lnd/issues/1002" rel="nofollow noreferrer">in earlier days lnd did not accept overpayments</a> as they seemed to not have implemented this part of the protocol. </p>

CC BY-SA 4.0
2019-02-27T14:14:45.210Z
Thank you Rene! Is this a way to know the fees paid by each routing node? 503 Satoshis in routing fees seems like an amount that is higher than I expected. Happy to see a fee market develop for LN though!
francois
CC BY-SA 4.0
2019-02-27T10:48:37.483Z
2019-02-27T10:48:37.483Z
Rene Pickhardt
<p>A friend sent me an invoice for 500,000 Satoshis. To my surprise, I sent 502294 Satoshis.</p>

<p>Here's what I see from my c-lightning console:</p>

<ul>
<li>"msatoshi": 500,000,000</li>
<li>"msatoshi_sent": 502,294,595</li>
</ul>

<p>My friend received a different amount on lnd:</p>

<ul>
<li>"value": "500000"</li>
<li>"amt_paid_sat": "501791"</li>
</ul>

<p>Any reasons why I am not sending the amount requested on the invoice? Also is my understanding correct that I paid 503 satoshis in fees for this transaction? It's more than I expected on the lightning network.</p>

<p>Thanks,</p>

<p>Francois</p>

<transaction-fees><lightning-network><core-lightning>
Why does my c-lightning node pay more than the invoice plus routing fees?
francois
# Why does my c-lightning node pay more than the invoice plus routing fees?

(Asked by: username_0 on 2019-02-27)

A friend sent me an invoice for 500,000 Satoshis. To my surprise, I sent 502294 Satoshis.

Here's what I see from my c-lightning console:

* "msatoshi": 500,000,000
* "msatoshi\_sent": 502,294,595

My friend received a different amount on lnd:

* "value": "500000"
* "amt\_paid\_sat": "501791"

Any reasons why I am not sending the amount requested on the invoice? Also is my understanding correct that I paid 503 satoshis in fees for this transaction? It's more than I expected on the lightning network.

Thanks,

username_0

**Tags:** transaction-fees, lightning-network, core-lightning


---

## 1 answers

### Answer by username_1 on 2019-02-27. Score: 4

In your c-lightning node you have configured your `maximum fee rate` which is used by the `pay` command to do the payment.

The [BOLT04](https://github.com/lightningnetwork/lightning-rfc/blob/master/04-onion-routing.md#failure-messages) describes how overpaying up to twice the amount to obfuscate payments in order to have better privacy is part of the protocol:

> if the amount paid is more than twice the amount expected:
> SHOULD fail the HTLC.
>
> SHOULD return an incorrect\_or\_unknown\_payment\_details error.
>
> Note: this allows the origin node to reduce information leakage by altering the amount while not allowing for accidental gross overpayment.

In combination with [this merged pull request](https://github.com/ElementsProject/lightning/pull/1257) c-lightning fixed [this issue](https://github.com/ElementsProject/lightning/issues/1089)
implementing random overpayments up to the maximum fee rate.

So generally c-lightning will randomly overpay your transaction with an amount that is lower to the maximum feerate you are willing to pay.

Not that [in earlier days lnd did not accept overpayments](https://github.com/lightningnetwork/lnd/issues/1002) as they seemed to not have implemented this part of the protocol.

> **Comments:**
> **username_0**: Thank you username_1! Is this a way to know the fees paid by each routing node? 503 Satoshis in routing fees seems like an amount that is higher than I expected. Happy to see a fee market develop for LN though!  

---

