Learn·Markets
What the swap fee is, and which side pays it
A per-subnet rate the pool takes on every trade, charged on what you send in — which is why the buy and sell depth figures never quite match.
Published 2026-09-17
Set per subnet, read per subnet
Every trade through a subnet's pool pays the pool a fee at a rate stored on chain for that subnet, Swap.FeeRate. It is a subnet parameter, not a network constant — it reads the same everywhere today, but nothing requires that, so Taosis reads it per subnet rather than assuming one figure.
Root (SN0) has no pool — it stakes one-to-one with τ — and no swap fee; every pool-shaped figure is blank for root.
Charged on what goes in
The fee comes off the input before it reaches the curve: off your τ when buying, off your α when selling, and the output is computed from the rest. The effective input is amount × (1 − swap fee).
That differs from a fee taken off what you receive; on a constant-product curve they are different numbers, and the difference shows in the depth columns.
Why depth is asymmetric
Lifting the price by a fraction δ needs the τ reserve to grow by √(1+δ); because the fee is taken first, a buyer must send that divided by (1 − swap fee). Up-depth = τ reserve × (√(1+δ) − 1) ÷ (1 − swap fee). Down-depth = τ reserve × (1 − √(1−δ)), with no division: that τ leaves the pool, and the fee was charged on the α going in.
So the down figure is always a little larger than the up figure at the same distance — fee treatment plus the curve's convexity, not an error. Without the subnet's own fee a depth is a different number, so Taosis then publishes none.
Where it appears, and what it is not
The screener's Liquidity group has a Swap fee column, each subnet page prints it beside the pool figures, and the compare table ranks subnets on it. The swap form's quote already has it inside.
It is not the Taosis fee, which is a surcharge on the network fee — the chain's charge for including the transaction — not on the trade, shown before you sign and collected in the same signed transaction, so a failed swap pays none. Pool, chain, Taosis: three different charges.
Read next
Pool depth and slippage
Depth is the τ that moves a pool's price a given distance; a quote is the same curve read from the trader's side, with the fee on a different leg for buys and sells.
How buying α works
Buying α is a stake call against the subnet's pool: τ goes in, α comes out, and it is staked to a validator from the first block.
Staking safely
What you are actually signing when you stake through Taosis, and what Taosis can never do with it.