Why projects give tokens away
A new protocol with a governance token faces a distribution problem: someone has to own it. Uniswap, the best documented example, said its early users would serve as stewards of the protocol; giving tokens to people who already used the product spreads ownership among real users. An airdrop does the second. The project picks a past date, records which addresses qualified, and lets those addresses claim or receive tokens.[1]
The best documented case is Uniswap. On September 16, 2020, it launched UNI with 1 billion tokens minted at genesis and made 15%, or 150 million UNI, immediately claimable by past users, liquidity providers and SOCKS holders, based on a snapshot ending September 1, 2020 at 12:00 am UTC.[1]
Airdrops also follow chain splits: the IRS ruling below deals with new tokens airdropped to holders after a hard fork. Not every token that lands in a wallet is an airdrop in this sense: anyone can send any token to any public address, which is why an unexpected balance proves nothing about a project's legitimacy.[2]
See also: Uniswap
How eligibility is decided
Every legitimate airdrop has two parts: a snapshot and a rule. The snapshot freezes the chain's state at a block or date. The rule says what counted, for example making a swap, providing liquidity, or holding a token. Uniswap used three rules: 400 UNI for each address that had called the v1 or v2 contracts, a pro-rata share of about 49 million UNI for liquidity providers weighted by liquidity over time, and 1,000 UNI for SOCKS redeemers and holders.[1]
That structure is the most useful fact for spotting fraud. Because the snapshot is in the past, a real project never needs you to act now to qualify. Claim periods exist, but the list of eligible wallets is already fixed when the airdrop is announced.[1]
Some airdrops must be claimed on the project's site, which means connecting a wallet and paying gas for the claim transaction. Others simply appear in wallets with no action, which is also how scam tokens arrive: ethereum.org describes scam projects airdropping a token and sending you to a site to claim it.
Because the list is fixed at the snapshot, no outside site can tell you in advance that a wallet will qualify for a future airdrop. Uniswap's list was published with the launch: 15% of supply, 150 million UNI, was claimable immediately by the addresses in the snapshot.[1]
Worked example: the UNI airdrop in numbers
Uniswap reported 251,534 historical user addresses, 49,192 historical liquidity providers and 220 SOCKS holders or redeemers. At 400 UNI each, the user allocation alone comes to 251,534 * 400 = 100,613,600 UNI, just over 10% of the 1 billion total supply.[1]
Add about 49 million UNI for liquidity providers and 1,000 UNI each for the 220 SOCKS addresses, which is 220,000 UNI, and the total lands near the 150 million, or 15%, that Uniswap announced. The arithmetic shows how airdrops really work: the budget is fixed up front and split by rules applied to history, not by who follows a social account after launch.[1]
If a US taxpayer treats a claim like the income described in the IRS ruling, it counts on the day they gain control. If 400 UNI were worth $3.00 each when claimed, that is $1,200 of ordinary income. The $3.00 price is illustrative; use the actual market price at the moment you gained control.[2]
US tax treatment
IRS Revenue Ruling 2019-24 addresses airdrops following a hard fork. A taxpayer who receives units of a new cryptocurrency has ordinary income in the year of receipt, equal to fair market value when the airdrop is recorded on the ledger, provided they can dispose of it. If the tokens land at an exchange that does not yet support them, income arises later, when you actually gain the ability to transfer or sell.[2]
The IRS digital assets page lists an airdrop related to a hard fork among the events that require answering yes to the digital asset question on Form 1040. That ruling is written for hard-fork airdrops, so for other airdrop types check current IRS guidance or a tax adviser. Brokers report digital asset sales on Form 1099-DA: gross proceeds for transactions on or after January 1, 2025, and basis for certain transactions on or after January 1, 2026.[3]
See also: Crypto tax software
Airdrop scams and how to spot them
The FTC warns that promises of free money or free cryptocurrency from strangers are fake, and that only scammers demand payment in cryptocurrency. It also flags unsolicited messages, impersonated celebrities and guaranteed returns. Each maps directly onto fake airdrops: a direct message announcing you qualified, a fee to release your tokens, a famous name promoting the claim.[4]
ethereum.org describes the giveaway scam, also called the 2-for-1 scam: send ETH to an address and receive double back, usually with a short deadline to create urgency. Its conclusion is blunt: giveaways are always scams, and funds sent to them are lost forever.[5]
On-chain, the dangerous step is the signature. Fake claim sites ask you to sign a token approval or a permit that lets them drain your tokens, and random tokens sent to your wallet often point to such a site. Never enter a seed phrase to claim anything, and ignore unknown tokens rather than trying to sell them.[5]
Fake airdrops also borrow real names. A scam site may copy a project's logo, use a domain one letter off, and cite a real snapshot to look credible. The FTC's advice to research a name before sending anything covers this case: find the project's official announcement yourself, and only then connect a wallet.[4]
A safe claiming checklist
Start from the project, never from a message. Open the project's site from a bookmark or its verified documentation, not from a link in a DM, email or reply. The FTC advises researching a company with words like review, scam or complaint before sending anything, and that applies to claim pages too.[4]
Use a separate wallet for claims. A fresh address with only enough ETH for gas limits what a malicious signature can take. If the airdrop requires the eligible address, move the claimed tokens to your main wallet or a hardware wallet afterward rather than connecting your main wallet to a new site.
Read what you sign. A claim should be a transaction that calls a claim function and costs gas. A request to approve spending of your existing tokens, or an off-chain permit signature, has nothing to do with receiving new ones. When the wallet prompt does not match the action you intended, reject it.
Record the value on the day you claim. The IRS ties income to the moment you can dispose of the tokens, so note the date, the amount and the market price at that time, and keep the claim transaction hash with your records.[2]
The bottom line
Airdrops reward past behavior, so the only safe way to receive one is to use protocols for their own sake and check announcements on the project's official site after a snapshot has already happened. Record every claimed token's value on the day you can move it, since the IRS may treat it as income, and treat every message telling you that you qualified as a phishing attempt until the official site confirms it. No one can promise that a protocol will ever airdrop.
See also: Crypto airdrops directory · Hardware wallets
Educational content, not financial advice. Crypto assets are volatile; do your own research.