All trades on Injective are subject to fee rebates, whereby the fee recipient always receives a flat 40% of the trading fee regardless of whether the trade constitutes maker or taker flow. Relayers who originate an order can set the fee recipient. Therefore, if an API trader sets their own address as the fee recipient, that 40% goes to the trader's bank (subaccount 0) address. If the trade is done on Exchange dApps such as Helix, the 40% fee goes to the address that the particular Exchange dApp has set as the fee recipient.
For maker trades, the trading fee for some pairs is currently negative (we will use -0.01% as the example value for the rest of this page). This consists of 60% to the maker and 40% to the fee recipient (again, on Exchange dApps such as Helix, this will be an address set by the Exchange dApp). Therefore, 0.006% of the trade value is rebated to the maker, and 0.004% to the fee recipient. For trades that set themselves as the fee recipient, makers receive the full benefit of the -0.01% fee for these pairs.
Consider an example whereby a trader places a limit order to purchase 1 BTC/USDT PERP at $50,000. If this limit order constitutes maker flow, it is eligible for the -0.01% maker trading fee. Assuming this trade takes place on Helix, the fee recipient is not the trader's own bank address. Therefore, the fee rebate on this trade is $50,000 * 0.0001 * 0.6 = $3. However, if this trade goes through by self relaying, the fee rebate is $5 (the full -0.01% of $50,000).
Let's assume a trader places a market buy order for 1 BTC/USDT PERP. Since this order constitutes taker flow, the trader is not eligible for the negative maker trading rate, but rather pays a small fee (we will use 0.05% as the example value for the rest of this page). If BTC is $50,000, this trading fee is $25. Of this $25, $10 (40%) goes to the fee recipient. If this trade goes through by self relaying, they receive that $10 and their effective trading fee drops to $15, resulting in an effective trading fee of 0.03%.
If the trader in the example above has tier 4 status, their taker fee is discounted by 20%, resulting in a trading fee of only $20 for the same trade. Of this $20, $8 goes to the trader's own address as the fee recipient, bringing the effective trading fee to 0.024% or $12.