A legacy Bitcoin address is an original format for Bitcoin addresses, starting with "1" and offering universal compatibility across Bitcoin wallets. While it remains widely used for its familiarity and ease, legacy addresses typically have higher transaction fees and larger data requirements than newer formats like SegWit and Taproot.
What to Know About Legacy Bitcoin Addresses
A legacy Bitcoin address is the original format that came with Bitcoin’s launch in 2009. It’s easy to spot a legacy address because it always starts with “1.” For example, a typical legacy address might look like this: 15e15hWo6CShMgbAfo8c2Ykj4C6BLq6Not.
Legacy addresses have specific features that affect how they work. Because they require full script and signature data, they generally incur higher transaction fees and take up more storage space. This added data makes legacy addresses less efficient than newer formats, like Segregated Witness (SegWit addresses). Despite these differences, legacy addresses remain a trusted option for many Bitcoiners.
How Legacy Addresses Are Generated With Bitcoin Wallets
You first need a private and public key to create a legacy Bitcoin address. The private key is a randomly generated 256-bit number hashed to form a unique hexadecimal code. It confirms ownership of Bitcoin in any transaction. Next, the public key is derived from the private key using elliptic curve multiplication, giving it a unique identifier for the wallet address.
The public key is then hashed twice for security—first with SHA-256 and then with RIPEMD160. For legacy addresses, a version byte (0x00) is attached to the hash to signal that it’s a legacy address. A checksum is added to detect errors, and the final address is encoded using Base58 to make it readable and remove confusing characters like "0" and "O" to avoid mistakes.
How Does a Legacy Address Differ From Other Address Types?
Legacy addresses work differently from newer formats like SegWit and Taproot. Each has distinct features and benefits. Legacy addresses are known for compatibility across wallets, which makes them a reliable choice for those needing ease of use. However, they typically come with higher transaction fees and take up more space, which can be a downside for very active users.
A native SegWit address or Taproot address might be the better option for users looking to save on fees and reduce transaction size. Read more about use cases for Bitcoin addresses on Leather.
Benefits and Drawbacks of Legacy Addresses
Here’s a quick breakdown of the pros and cons of legacy Bitcoin addresses:
Legacy Address Benefits
Supported across Bitcoin wallets for high compatibility.
Reliable and well-known since Bitcoin’s early days, with broad support across platforms.
Legacy Address Drawbacks
Higher transaction fees than newer formats, impacting very active users.
Larger transaction sizes due to added data requirements make them less efficient for storage.
Why Are Legacy Addresses Still Used?
Here are three key reasons people still use legacy Bitcoin addresses:
Universal compatibility: Legacy addresses work with all Bitcoin wallets, allowing transactions to go through without compatibility issues.
Familiarity: Legacy addresses are familiar to long-time Bitcoin users, making them a comfortable choice for those who have been around since Bitcoin’s early days.
Accessibility: They provide a stable option for users who prioritize consistency over savings in transaction fees or speed.
How to Send and Receive Bitcoin with a Legacy Address
Sending Bitcoin to a legacy address is simple. Using an exchange or Bitcoin wallet like Leather, enter the recipient’s address, specify the amount, and confirm the transaction. Legacy addresses are compatible with all other address types so that users can send and receive Bitcoin from any format, including SegWit and Taproot.
To receive Bitcoin with a legacy address, simply give your legacy address to the sender, and they can transfer BTC without checking wallet compatibility. This ease of use and versatility is why legacy addresses remain popular for many Bitcoin users.
Future of Legacy Addresses in Bitcoin
Legacy addresses will remain part of Bitcoin’s network even as formats like SegWit and Taproot grow in use. Their universal compatibility means wallets, exchanges, and services built on Bitcoin’s original infrastructure will continue to support them.
As Bitcoin’s technology advances, legacy addresses may eventually see less use in favor of more efficient formats. Future upgrades could further improve SegWit and Taproot, attracting more users to these newer address types.