Fees
Fees play a crucial role in the incentive structure of both Bitcoin and JoinMarket. They form the basis for the economic incentives of both systems. In Bitcoin, you pay fees to a miner in order for your transaction to be included in a block. The higher the fee you are willing to pay, the higher the likelihood that your transaction will be included quickly.
In JoinMarket, you pay fees to market makers in order to use their liquidity to both of your advantage. However because the market maker gets the fee as he is waiting around and providing the liquidity.
Consequently, when you are sending a collaborative transaction in Jam—or when you are using the scheduler to do multiple transactions—you have to pay fees to miners and makers. How high these fees are depends on market and mempool conditions.
Of course, you can offer liquidity yourself via the Earn functionality, allowing you to be on the receiving end when it comes to maker fees.
Paying Maker Fees
When doing a collaborative transaction via the Send or Sweep tabs, you are taking liquidity offers from others, effectively becoming a market taker.
How much you will pay in maker fees depends on the fee market of the current offers. You can get an overview of fees by inspecting the order book.
FAQ: How high are the fees that I do have to pay?
Paying Mining Fees
Just like all users of onchain bitcoin, you will have to pay transaction fees to miners.
Note that collaborative transactions are larger, in terms of bytes, than "regular" bitcoin transactions. Since the cost of an onchain transaction is determined by its size in bytes—not by value transferred—a collaborative transaction is more expensive than a simple spend.
FAQ: How high are the fees that I do have to pay?
Earning Maker Fees
As mentioned above, you can use the Earn tab to earn maker fees yourself. Simply choose an offer type, select how many fees you would like to earn, and press "Start Earning!".
Make sure to check the orderbook to compare your offer with current market rates. If your offer isn't competitive, it's likely nobody will take it and thus you will earn zero sats.
Fee Conversion
All fees are denominated in sats. Use one of the tools below to convert them to fiat:
See also "a note on fees" from the JoinMarket documentation.