Blockchain and DEX fees

In this guide, you’ll learn how fees on STON.fi really work: what GRAM is temporarily reserved vs. actually consumed for swaps and liquidity provision, the typical cost ranges, and how pool (DEX) fees

In short:

✅ You always need a bit of GRAM to cover on-chain (network) fees.

✅ We reserve slightly more than the final fee so your transaction won’t fail; unused GRAM is auto-refunded.

✅ Swaps: we reserve up to ~0.35 GRAM; typical actual cost is ~0.06–0.09 GRAM, but can reach ~0.13 GRAM depending on the pool’s fee.

✅ Providing liquidity: we reserve per token (two reservations), usually up to ~0.7–0.8 GRAM total; typical actual cost is ~0.10–0.13 GRAM.

✅ DEX/trading fee (pool fee) is set per pool by its owner. A common setting is 0.30%; typically 0.20% goes to LPs and 0.10% to STON.fi, but the exact split follows the pool’s configured fee.

Why more GRAM is “reserved”

TON network fees aren’t perfectly predictable upfront. To avoid failed transactions:

• We temporarily reserve a bit more GRAM (the “cap”).

• The unused part is sent back to you automatically right after execution.

💡 Think of it like tapping your card at a gas station: a higher hold first, then a final charge for what you actually used.

Swaps

• Reservation (cap): up to ~0.35 GRAM (can vary by route/pool).

• Typical actual network fee: ~0.06–0.09 GRAM.

• Upper bound in some cases: ~0.13 GRAM.

• What drives it: the pool’s configured trading fee (set by the pool owner) and route complexity.

Any unused portion of the reservation is refunded.

Providing Liquidity

• Two signatures, two network actions (one per token). Network fees are reserved separately for each token, it makes two reservations in total. Costs refer to adding liquidity; removing liquidity typically incurs slightly lower network fees.

• Total reservation: usually up to ~0.7–0.8 GRAM (both tokens combined).

• Typical actual network fee (total): ~0.10–0.13 GRAM.

• What drives it: pool configuration and whether you’re using balanced vs. arbitrary provision.

As with swaps, unused GRAM is refunded automatically.

DEX / Trading Fee (Pool Fee)

• Who sets it: pool owner.

• Common configuration: 0.30% per swap.

• Where it goes: typically ~0.20% to LPs and ~0.10% to STON.fi.

• But: the exact fee and split follow the pool’s current settings.

🔍 You can see the trading fee in the pool details before you swap or add liquidity.

Practical tips

✅ Keep a small GRAM buffer for fees (even if you mainly hold jettons).

✅ Check the pool’s fee (0.30% is common, but not guaranteed).

✅ Expect a higher reservation on first tries or complex routes; the final spend is usually lower.

✅ If a transaction fails, reserved GRAM is automatically returned — you don’t lose it.