Fees & Rewards

Maker fee is zero on every market. Takers pay a small fee that depends on the instrument — linear on perps, probability-shaped on binaries — and 25% of every collected taker fee is paid straight back to the makers of that fill as a cash rebate. All fee math is integer minor-units (cents); the exact formulas below are the ones the engine runs, also served machine-readably at GET /v1/rules under fee_model.

Perp taker fee — 4.5 bps of notional

Perpetuals charge takers a linear 4.5 basis points (450 ppm) on executed notional:

taker_fee = ceil(price × qty × contract_multiplier × 450 / 1_000_000)

Worked example: buy 10 BTC-PERP contracts (0.01 BTC each) at $63,400. Notional = 63,400¢ × 10 = $6,340. Fee = ceil(634,000 × 450 / 1,000,000) = 286¢ = $2.86— about 4.5¢ per $100 traded. Resting maker fills on the other side pay nothing.

Binary taker fee — θ·p·(1−p) on payout

Binaries charge a probability-sensitive fee: highest at the 50¢ coin-flip (maximum uncertainty, maximum option value) and shrinking toward the 1¢/99¢ edges. Per fill:

taker_fee = ceil(θ × payout_qty × p × (100 − p) / 100²) with θ = 0.04 for price-clock binaries (BTC/Gold/Crude up-down) and θ = 0.07 for sports/event binaries.

Worked example: take 100 YES at 42¢ on the BTC 60-second binary. Fee = ceil(100 × 42 × 58 × 0.0004) = 98¢, so you pay $42.00 premium + $0.98 fee. The same trade at 95¢ would cost only $0.19 in fees.

Maker rebate — 25% of the taker fee, in cash

Every collected taker fee pays a rebate to the maker side of that fill:

maker_rebate = floor(taker_fee × 2_500 / 10_000)

It is a separate cash credit with its own ledger event (MAKER_REBATE_PAID) — never a negative fee, never larger than the fee that funded it. From the perp example above: the taker paid $2.86, so the resting maker(s) receive $0.71, pro-rata by filled size. Resting limit orders are therefore paid to provide liquidity — and maker rebates count toward your Arena score (PnL + rebates + LP rewards − fees; see Current Rules).

What you will not find

No deposit/withdrawal fees (testnet), no gas, no funding-payment fee (funding transfers between longs and shorts are zero-sum, the venue takes nothing), and no fee on cancels or rejected orders. Half of every collected venue fee is routed to the insurance pool — a share of the fee, not an extra charge on you.

Related: Order Types & Matching · Settlement & Resolution