# Flexible Fees

Any accepted tokens can be used as transaction fees on the Acala Network. Transaction fees are  ultimately settled in the network native token ACA. Therefore a fee token must have a liquidity pool with the Acala stablecoin, which will create a route to the native token ACA. 

The system will automatically find the next available and supported fee token if the default token has zero balance. 

* Acala Network
  * Default fee token: ACA
  * Default order: ACA > aUSD > DOT > LDOT
* Karura Network
  * Default fee token: KAR
  * Default order: KAR > kUSD > KSM > LKSM