Every Bitcoin transaction must be packaged and confirmed by miners before it is completed. However, as more and more people use Bitcoin, the total size of pending transactions has far exceeded the network’s block capacity, resulting in severe congestion on the Bitcoin network. Miners usually prioritize transactions with higher fees, while transactions with fees that are too low may remain unconfirmed for a long time.

Common reasons for free acceleration failure：

1. Transaction fee too low: Only transactions with a fee of at least 0.0001 BTC/KB can be accelerated;
2. Transaction size too large: Free submission is only available for transactions ≤ 0.5 KB;
3. Free quota exhausted: 0 free accelerations are available per hour. Please resubmit at the start of the next hour or use paid acceleration instead;
4. Previous transaction unconfirmed: If your current transaction includes an unconfirmed input, it cannot be confirmed. We recommend accelerating the previous transaction first or using paid acceleration instead.

In addition, double-spend transactions are not supported for acceleration.

Since transaction acceleration cannot be canceled once submitted, this service is non-refundable.

ViaBTC partners with multiple leading mining pools to provide industry-leading BTC transaction acceleration services. If your transaction is confirmed by a mining pool other than ViaBTC, it may have been accelerated by one of our partners.