Perpetuals vs Options Fees

Builder fees work on both perpetuals and options, but they are calculated differently. The difference is what the fee rate is applied to.

Perpetuals

builder fee = fee rate × trade price × contracts

A straight percentage of the trade's notional. For example, at 3 bps, one ETH-PERP contract traded at $2,700 pays a builder fee of $0.81.

The rate can't exceed the protocol cap for perpetuals: 5 bps (max_fee_rate_perps = 0.0005).

Options

builder fee = min(
  fee rate           × index price × contracts,
  option premium cap × premium     × contracts
)

The rate is applied to the underlying's index notional, not to the option's premium. That is how options fees are normally quoted, and it is the same way Aevo charges its own options trading fee.

On its own, an index-based fee would be unfair on cheap options: 3 bps on one ETH contract is $0.81 whether the option costs $100 or $1. So the builder fee is also capped at a share of the premium (option_premium_cap), and the smaller of the two applies.

Options have their own, separate caps: a rate of at most 3 bps of index notional (max_fee_rate_options = 0.0003), and a fee of at most 5% of the premium (option_premium_cap = 0.05). Builder fees on options are available only while both option settings are configured.

Example

ETH index $2,700, 1 contract, builder fee rate 3 bps, option premium cap 5%:

Premium	Index-based fee	5% of premium	Builder fee	Share of premium
$100	$0.81	$5.00	$0.81	0.8%
$20	$0.81	$1.00	$0.81	4.1%
$5	$0.81	$0.25	$0.25	5%
$1	$0.81	$0.05	$0.05	5%

The two limits cross where the premium equals fee rate × index price ÷ option premium cap, which is $16.20 in this example. Above that premium the index-based fee applies; below it, the premium cap applies. On cheap, out-of-the-money options, builders earn well below the headline rate.

Side by side

	Perpetuals	Options
Fee based on	Trade price × contracts	Index price × contracts
Protection for cheap trades	Not needed	Capped at a share of the premium
Maximum rate	5 bps (max_fee_rate_perps)	3 bps (max_fee_rate_options)
Maximum share of premium	—	5% (option_premium_cap)
Dashboard volume	Trade price × contracts	Index price × contracts

Current values of every cap are published at GET /builder-config.

One approval, two limits

A user's approval covers both perpetuals and options, but each order must also fit the cap for its instrument type. If the options cap is lower than the user's approved maximum, option orders are limited by the options cap.

For example, if a user approves the maximum of 5 bps, a builder can charge them up to 5 bps on perpetual orders but at most 3 bps on option orders. An option order above 3 bps is rejected with BUILDER_FEE_EXCEEDS_AEVO_LIMIT.

Sending the rate

Builders send the fee the same way for perpetuals and options: the same builder_id and builder_fee_rate fields, as a decimal string such as "0.0003", signed the same way. Aevo decides how to apply it from the instrument.

On an option order, builder_fee_rate is a rate on index notional, not on the premium. Send only the rate, never a fee amount; Aevo applies the premium cap on each fill. See Placing orders.

Tips for builders

• Price options separately. Your perpetuals rate doesn't carry over to options.

• Expect lower fees on cheap options. The premium cap applies below the crossover premium.

• Option volume looks large next to its fees. Dashboard volume for options is index notional, the same basis as the fee, not premium.