TL;DR
A burner wallet is a temporary, disposable wallet used for risky interactions like new token launches, unknown dApps, or airdrop claims, isolating risk from your main holdings.
Every time you connect a wallet to a dApp and sign a transaction, there’s risk — the site could be a drainer, the token could be a honeypot, or a smart contract could have a vulnerability. A burner wallet limits your downside: if it’s compromised, you only lose what’s in that wallet. Your main holdings in a separate wallet remain safe because they’ve never interacted with the risky contract.
Create a new wallet in Phantom (or any wallet) — it takes seconds. Send only the SOL you plan to use for the specific transaction. Do your risky interaction. If everything goes well, send profits back to your main wallet. If the burner gets compromised, the loss is limited. Some traders maintain several burner wallets for different purposes: one for launches, one for airdrop claims, one for new dApps.
Never keep more in a burner than you’re willing to lose. Don’t reuse burners for unrelated interactions — this links your activity. Transfer profits to your main wallet promptly. Consider the burner compromised after interacting with any sketchy site. For Pump.fun trading, many traders use a dedicated trading wallet separate from their long-term holding wallet.