Coinbase began implementing SegWit across our platform on Wednesday, February 21, 2018. We will progressively update all customer Bitcoin addresses to be SegWit-compatible (SegWit addresses) over the following week.
What is Segregated Witness (SegWit)?
Segregated Witness--more commonly known as SegWit--is an upgrade to Bitcoin that makes transactions more secure and efficient. By separating (segregating) the main part of the transaction data from the part which authorizes the transaction (witness), the entire transaction becomes more secure. Separating the two parts also makes the transaction data smaller, and thus allows more transactions to be sent at once.
As the Bitcoin community continues to adopt SegWit, the Bitcoin blockchain will be able to process more transactions. Coinbase transactions will be sent more quickly, and the increase in throughput will reduce the overall network fee required for each transaction.
How does this affect me?
The process of sending and receiving Bitcoin will remain the same. We expect that customers sending Bitcoin from Coinbase will pay less in fees to the network on average when sending their transactions. Though there are many factors that go into determining the network/miner fee, this change will help reduce the size of the fee required in order to prioritize your transaction. Overall network throughput is expected to improve, reducing the chance of delays.
Are my funds safe?
Yes, all Bitcoin stored on Coinbase is safe and unaffected by this change.
If you are sending Bitcoin Cash to Coinbase, please see the important warning below, "What happens if I send BCH to a SegWit address"
What happens if I send BCH to a SegWit address?
If you incorrectly send Bitcoin Cash (BCH) to a SegWit (BTC) address, your funds will not be recoverable. The changes introduced by SegWit are incompatible with Bitcoin Cash, and it is impossible to access any Bitcoin Cash which has been lost in this way.
Does anything change with the way that I send Bitcoin?
No. When sending Bitcoin from Coinbase to an external address, we will automatically send your transaction using SegWit. Because SegWit is backwards compatible with previous Bitcoin addresses, you can safely send transactions from Coinbase to any external Bitcoin address or wallet.
When receiving Bitcoin in your Coinbase account from an external source, we will provide a SegWit address. This address is compatible with BTC wallets.
Any manipulation of Coinbase addresses will not be supported.
Will I be able to send Bitcoin to Coinbase from a non-SegWit address?
Yes. You can send to the Bitcoin receiving addresses for your Coinbase account from any external Bitcoin address or wallet.
Does SegWit allow me to send other assets besides Bitcoin to my BTC address?
No. Digital assets sent to the wrong currency address will result in permanent loss of those assets.