Two Directions of ENS Resolution
ENS resolution works in two directions, and they are independent of each other.
Forward resolution goes from name to address: alice.eth → 0x1234.... This is what happens when someone types your ENS name into a wallet app to send you funds.
Reverse resolution goes from address to name: 0x1234... → alice.eth. This is what happens when a dApp or wallet looks at your wallet address and tries to display a human-readable name instead of the raw hex.
A primary ENS name controls the reverse resolution. Without setting one, apps that look up your address will show nothing — just the 0x address.
What Actually Changes When You Set a Primary Name
Once your primary name is set, any app that performs reverse ENS lookups will display your name instead of your address. In practice this means:
- MetaMask shows your .eth name in the account header
- OpenSea displays your name on your profile and in transaction history
- Uniswap and most major DEX interfaces show your name next to trade history
- Farcaster, Lens, and other social apps use it as your default identifier
- Anyone who pastes your address into app.ens.domains sees your primary name linked
The change is immediate once the transaction confirms. No extra steps are needed on each platform.
How to Set a Primary Name
Go to app.ens.domains and connect your wallet. Under your profile, you will see a "Primary Name" section. If you have multiple ENS names pointing to your address, you can choose which one to set as primary. Select the name, confirm the transaction, and the reverse record is set on-chain.
Gas cost for this operation is typically $2–10 on Ethereum mainnet, depending on network conditions.
For Basenames, the same concept applies. Go to base.org/names, connect your wallet, and set your Basename as primary. Because this runs on Base (L2), the gas cost is negligible.
Note that you can have an ENS primary name and a Basenames primary name at the same time — they are on different chains and do not conflict. Apps that support ENS resolution on Ethereum mainnet will use your ENS primary; apps that are Base-native will prefer your Basenames primary.
The ENSIP-19 Upgrade
In late 2025, ENS implemented ENSIP-19, which introduced standardized L2 primary name support. Before this, setting a Basename as your primary name required an expensive Ethereum mainnet transaction. After ENSIP-19, the process runs natively on Base and costs next to nothing.
If you set a Basename primary name before the ENSIP-19 migration, your existing record should have been migrated automatically. If you are setting one for the first time, the updated flow at base.org/names uses the L2-native method.
Multiple Names, One Primary
You can own many ENS names but only one can be your primary. Choose the one that represents you most clearly — your personal name, your main project name, or your most recognizable handle.
If you run a project where multiple team members need ENS identities, each person sets their own primary name on their own wallet. The project itself can also register a name (project.eth) and use it as a payment address, but a project name cannot serve as a primary name for an individual wallet in the same way.
Check Your Name Situation First
Before going through the setup process, it helps to confirm what is available and what you already hold. This tool shows availability for any list of names on both ENS and Basenames, so you can verify the name you want is actually registerable before committing.