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

# Hearth, fees, and HEAT CD yield

> How Hearth and swapXFG fees fund HEAT CD yield under live constants.

## Real yield, not emissions

HEAT CD yield is paid from **fees**, not token printing.

## Two fee engines

### 1) swapXFG (cross-chain)

* Rate: **1%** of XFG side (`SWAP_FEE_RATE_BPS = 100`)
* Split: **69% CD · 11% Bonus Vault · 20% Treasury**

### 2) Hearth (XFG/HEAT on-chain)

* Rate: **1%** (`HEARTH_FEE_BPS = 100`)
* Split: **100% CD · 0% LP** (LPs earn the swap spread, not the fee)

## User path

```
Mint HEAT from XFG (Hearth TWAP)
  → Lock HEAT CD (6–72 epochs mainnet)
  → Fees from swaps + Hearth accrue to CD pool
  → Withdraw or rollover at maturity
```

## Epochs

Mainnet epoch = **900 blocks** (\~5 days at \~480s). Distribution and accounting are epoch-scoped.

## Superseded claims (do not use)

The following are **incorrect** for current code and must not be treated as product facts:

* Hearth protocol trade fee of 0.3% (live: **1%** `HEARTH_FEE_BPS`, 100% CD / 0% LP)
* Atomic swap fees “80% to CDs only” (live: **69% CD / 11% Bonus / 20% Treasury**)
* Opening a CD by locking **XFG** (live: lock **HEAT** after mint)

## Further reading

* [How Hearth works](/features/hearth/how-hearth-works)
* [Interest and yield](/features/commitment-deposits/interest-and-yield)
* [Fee pool API](/api-reference/fee-pool)