there are 2 different type of fees in cashu:
1. Is the lightning fee. It is hard to predict the actual fee before completing the payment, which is why the protocol uses a `fee reserve`, like a max fee your wallet will allow to be paid. If not all of the fee reserve is used for the lightning payment, the mint will issue fresh ecash to you for the reserve/actual delta
2. Mints can optionally charge fees for swaps. Not all mints charge fees, since it's currently being used as mainly a spam prevention mechanism. To understand swap ecash fees, you have to know when a swap happens:
- You want to make a payment, but don't have the coin denominations that add up to the amount you want to send
- You want to receive a token (burn the senders ecash)
So if you send a token, that doesn't need to be swapped (you have the exact change) as a sender you have no fees. The receiver however will have to pay the fee to perform the swap.
Receiving always requires a swap, since that is the double spending prevention mechanism
gandlaf21
npub1cj…886t6
2025-05-04 07:58:50
in reply to nevent1q…re7y
Author Public Key
npub1cj6ndx5akfazux7f0vjl4fyx9k0ulf682p437fe03a9ndwqjm0tqj886t6Published at
2025-05-04 07:58:50Event JSON
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"pubkey": "c4b5369a9db27a2e1bc97b25faa4862d9fcfa747506b1f272f8f4b36b812dbd6",
"created_at": 1746345530,
"kind": 1,
"tags": [
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[
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"content": "there are 2 different type of fees in cashu:\n\n1. Is the lightning fee. It is hard to predict the actual fee before completing the payment, which is why the protocol uses a `fee reserve`, like a max fee your wallet will allow to be paid. If not all of the fee reserve is used for the lightning payment, the mint will issue fresh ecash to you for the reserve/actual delta\n\n2. Mints can optionally charge fees for swaps. Not all mints charge fees, since it's currently being used as mainly a spam prevention mechanism. To understand swap ecash fees, you have to know when a swap happens: \n\n- You want to make a payment, but don't have the coin denominations that add up to the amount you want to send \n- You want to receive a token (burn the senders ecash)\n\nSo if you send a token, that doesn't need to be swapped (you have the exact change) as a sender you have no fees. The receiver however will have to pay the fee to perform the swap.\n\nReceiving always requires a swap, since that is the double spending prevention mechanism",
"sig": "8f349ddb24dd45f5e07e0a08c009f2392141d5a7395080a08232dd2a8edde09dfeb5c27c8502e0c7fe169a31d0266b94e532fe4de14c8b0c8a6b01fcad2f13d2"
}