We recommend at least 0.015 BTC per deposit to help avoid higher withdrawal fees in the future.
Caution: If you have a legacy vault (built prior to the 21st of February 2025), we recommend a higher minimum deposit of 0.03 BTC. You can tell if your vault is a legacy vault based on whether or not it has a legacy indicator. If you have a legacy vault and want to migrate to a newer (segwit) vault, please see our guide.
Each deposit to a self-custody bitcoin wallet adds one UTXO (or "chunk of bitcoin") to that wallet. If the UTXO has a large value, then when it is spent, only a small percentage of the value will need to be used for transaction fees.
On the other hand, if the UTXO has a small value, a larger percentage of the value will need to be used for transaction fees. If bitcoin network fee rates are high and the UTXO is small enough, a majority of the value of the UTXO could be eaten up by fees. A UTXO like this is sometimes called "dust."
Learn: You can better understand the dangers of small UTXOs by reading our blog article, and explore the math behind bitcoin dust in another one of our articles here.
To prevent yourself from holding dust or experiencing high transaction fees, avoid making small deposits. Instead, deposit bitcoin less frequently and in larger amounts.
For an Unchained vault, we recommend making deposits of at least 0.015 BTC (0.03 BTC for legacy vaults). If the average UTXO in your vault has a value above this amount, you are less likely to experience high transaction fees from dust UTXOs.