Every transaction on the XRP Ledger must include a Fee field specifying how much XRP will be destroyed. The minimum required is 10 drops (0.00001 XRP) for standard transactions. This fee is not paid to validators — it is permanently burned, reducing XRP's total supply.

The fee calculation uses the formula: Current Cost = (base_fee × load_factor) ÷ load_base. Under normal conditions, the load_factor equals the load_base, making the effective fee exactly the 10-drop base. During high load, the load_factor rises, increasing costs proportionally.

Validators independently estimate how many transactions can be processed per ledger. When demand approaches the capacity threshold — around 200 transactions per ledger — the exponential fee escalation curve activates. Fees can rise sharply but return to the base rate once congestion clears.

This design serves a dual purpose: protecting the network from spam attacks by making mass-transaction attacks economically costly, while keeping normal user fees essentially free. The burning mechanism also creates mild deflationary pressure on XRP supply over time.