> ## Documentation Index
> Fetch the complete documentation index at: https://docs.raydium.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Stable AMM fees

> Identical to AMM v4: 0.25% trade fee, 0.22% LP / 0.03% protocol split. No fund fee, no creator fee.

## The fee model

Stable AMM uses **the same fee structure as AMM v4**. There is only one fee tier per pool (set at initialization); pools cannot be reconfigured into higher tiers.

| Field                                               | Default       | Meaning                                                                                               |
| --------------------------------------------------- | ------------- | ----------------------------------------------------------------------------------------------------- |
| `swap_fee_numerator / swap_fee_denominator`         | `25 / 10_000` | **Gross trade fee: 0.25%** of input volume.                                                           |
| `trade_fee_numerator / trade_fee_denominator`       | `25 / 10_000` | Same 0.25%; legacy field formerly used for OpenBook order pricing, retained for layout compatibility. |
| `pnl_numerator / pnl_denominator`                   | `12 / 100`    | **Protocol's share of the fee: 12%** — i.e., `0.25% × 12% = 0.03%` of volume.                         |
| `min_separate_numerator / min_separate_denominator` | `4 / 10_000`  | Internal rounding floor.                                                                              |

There is **no fund-fee** and **no creator-fee** line — these are post-AMM v4 inventions (CPMM/CLMM). Stable AMM predates that convention.

## How the split is computed

On each swap:

```
gross_fee = ceil(amount_in * (swap_fee_numerator / swap_fee_denominator))    // e.g., 0.25% of amount_in
pnl_portion = gross_fee * (pnl_numerator / pnl_denominator)                  // 12% of gross_fee
lp_portion = gross_fee − pnl_portion                                          // 88% of gross_fee
```

* **`lp_portion`** stays in the vault, inflates `k`, and benefits LPs on redemption.
* **`pnl_portion`** increments `AmmInfo.out_put.need_take_pnl_coin` or `need_take_pnl_pc` (depending on the input token) and is swept by `WithdrawPnl`.

Same **invariant-preserving trick** as CPMM: the PnL amount sits in the vault physically but is subtracted from the "effective reserves" used in the curve math, so removing it does not shift the price.

## OpenBook PnL (retired)

Early in its life, the pool also posted limit orders on OpenBook; when those filled, it earned or lost the market-maker/taker spread, settled during `MonitorStep`, and tracked the result in the `out_put.total_pnl_{coin,pc}` counters. **That path has been dormant for years** — the pool holds no open orders, so the only fee accrual is the 0.03% protocol share described above. The `total_pnl_*` counters remain in the layout but no longer increment. The [2026-06-22 upgrade](/reference/changelog) removed the leftover OpenBook code (including `MonitorStep`). CPMM became the default for new pools partly because of this former coupling to OpenBook; Stable AMM is order-book-independent.

## Collection

The Raydium multisig (or whoever controls `amm_admin`) calls `WithdrawPnl` to sweep:

1. Transfers `need_take_pnl_coin` and `need_take_pnl_pc` from vaults to admin-designated accounts.
2. Zeroes the counters.

The operation does not move the curve. LPs see no price change.

<Warning>
  `WithdrawPnl` was changed in the 2026-06-22 upgrade: it now uses a **fixed 10-account, admin-only layout with no compatibility path** (old layouts fail with errors such as `InvalidTokenCoin`), and when the pool's available funds are insufficient to cover the PnL it returns `TakePnlError` directly instead of disabling the pool. See [`products/stable/instructions`](/products/stable/instructions#withdrawpnl).
</Warning>

## LP fee redemption

No dedicated "collect fees" instruction. LP fees accumulate in vaults, inflating the reserves. LPs realize them by burning LP via `Withdraw`. The value of an LP token grows as reserves grow.

## Visualization: where \$1,000 of volume goes

On a USDC-heavy `Swap` of \$1,000 against a default-parameter Stable pool:

```
Gross trade fee (0.25%):     $2.50
  LP share   (0.22%):         $2.20  → stays in pool, raises k
  PnL share  (0.03%):         $0.30  → need_take_pnl_pc, swept by WithdrawPnl
User receives (minus curve):  $997.50
```

Compare to AMM v4 (identical) and CPMM (0.25% tier, no creator fee): CPMM gives LPs \$2.10, protocol \$0.30, fund \$0.10.

## Comparison table

|           | Stable AMM | AMM v4 | CPMM `index=0` |
| --------- | ---------- | ------ | -------------- |
| Trade fee | 0.25%      | 0.25%  | 0.25%          |
| LP        | 0.22%      | 0.22%  | 0.21%          |
| Protocol  | 0.03%      | 0.03%  | 0.03%          |
| Fund      | None       | None   | 0.01%          |
| Creator   | None       | None   | 0 by default   |

Full matrix: [`reference/fee-comparison`](/reference/fee-comparison).

## Integrator notes

* **Quoting:** Always read `AmmInfo` from the chain; do not hardcode fees. With `SetParams` now removed, the fee parameters on existing pools are effectively fixed.
* **Curve vs. fees:** The 0.25% fee is independent of whether the curve is a formula (x·y=k in AMM v4) or a lookup table (Stable). Both apply the same 0.25% to the input amount.
* **No rewards:** Stable pools do not support on-pool reward emissions. Ecosystem farms (Farm v3/v5/v6) handle staking elsewhere.

## Where to go next

* [`products/stable/math`](/products/stable/math) — fee application in swap math.
* [`products/stable/instructions`](/products/stable/instructions) — `WithdrawPnl` account list.
* [`products/amm-v4/fees`](/products/amm-v4/fees) — deeper fee derivation for OpenBook path.
* [`reference/fee-comparison`](/reference/fee-comparison) — side-by-side all products.

Sources:

* `raydium-stable/program/src/state.rs` (`Fees` struct)
* On-chain `AmmInfo.fees` fields on live mainnet pools