# Affiliate Fee

On the **Optimex** transactions that a wallet provider builds for their users, the wallet provider can add an affiliate fee. This fee is independent from the protocol fee and is paid by the users.\
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The affiliate fee is indicated in basis points, and will be collected by **Optimex** protocol on the wallet provider behalf.\
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In case users trade their BTC for other asset, the affiliate fee shall be collected in the PMM payment sent to the user. Alternatively, when the user swap other tokens for BTC, the affiliate fee will be collected by the **Optimex** Vault (which is implemented using a smart contract) that holds user funds during the trade.\ <br>