Sonic is the network built by the team formerly known as Fantom. It uses the same address format as Ethereum, so one paste covers your position on the chain.
Fees are paid in S, the network's own token. If you held FTM, you swapped it for S one for one through the upgrade portal, and the price you paid for the FTM carries across.
One thing worth knowing before you start: Sonic is a new network rather than a renamed one. Fantom Opera is still running, and if you left anything behind there it needs importing separately.
What you get out of the box
Pick your import method.
On Sonic
- Open your wallet and copy your address. It starts with 0x and is the same address you used on Fantom.
- If you still hold anything on Fantom Opera, add that as a separate wallet too. Same address, different network.
On Kryptos
- Go to Kryptos.io and sign up with your Google account.
- From the menu, click Integrations.
- Click Add Integration and search for Sonic.
- Click the Sonic icon, then choose Import using Address.
- Give the wallet a name, paste your address, and click Import Your Transactions.
Good to know
- Sonic and Fantom Opera are two live networks sharing one address. Adding one does not import the other.
- The FTM to S swap runs one way now. You can still move FTM to S, but not back.
- Airdrop claims can arrive in pieces over many months, so your claimed total may not match the amount you were allocated.
Fantom did not become Sonic, exactly
The shorthand everyone uses is that Fantom became Sonic. It is close enough for conversation and wrong enough to lose money over.
Sonic is a new network that launched in December 2024. Fantom Opera, the original chain, is still producing blocks. Two live networks, one address, and no automatic movement between them. Anything you left on Opera is still sitting on Opera.
This matters twice. It matters for balances, because a portfolio that only imports Sonic will be missing whatever stayed behind. And it matters for the token swap, because moving FTM to S is something you do deliberately through the upgrade portal, not something the network does for you.
If you are not sure, add the same address on both networks and see what turns up. Our Fantom integration covers the Opera side.
The airdrop that shrinks if you take it early
Most airdrops hand you a number and you claim it. Sonic's does something less common, and it changes the arithmetic on your tax return.
Three quarters of an allocation matures over 270 days. Claim it before then and a portion is burned, permanently. Wait and you get the full amount. So the number you were allocated and the number that reaches your wallet can be quite different, and the gap is not a fee you can deduct anywhere. The tokens were never yours.
For your report, work from the wallet. Whatever arrived, on the date it arrived, at that day's price. Ignore the allocation figure entirely: it is a promise, not a receipt. Claims that came in tranches produce several separate acquisitions at several different prices, which is tedious by hand and exactly the sort of thing Kryptos reconstructs from the chain.
For how airdrop income is treated where you file, see the USA crypto tax guide or the UK crypto tax guide.
Manage your Sonic portfolio with Kryptos.
Upgrading FTM to S
The swap runs one for one through the upgrade portal. It replaced your token without changing what you owned, so the original FTM cost should carry over rather than resetting.
Claiming the Sonic airdrop
Claims could be taken early at a cost or waited out in full. Either way, what matters is what landed in your wallet and when, not what you were allocated.
Staking S with a validator
Rewards are claimed rather than compounded, and unstaking takes two steps with a wait in between. Each claim is a receipt on the day it arrives.
Audit-ready, automatically.
Once your wallets and exchanges are connected, generating a tax report takes a single click. Open Reports from the menu, choose your jurisdiction, and download.
The FTM upgrade is a substitution
Swapping FTM for S one for one continued the same holding under a new name. Carry the FTM purchase price into the S rather than treating the swap as a sale and a fresh buy.
Claim what you received, not what you were offered
Taking the airdrop early burns part of it. The amount that reaches your wallet is the amount you received, and that is what goes on your return. The headline allocation does not.
Staking rewards are receipts when claimed
Sonic rewards do not roll into your stake by themselves. You claim them, and the claim is when you receive them, valued that day.
Unstaking is not a disposal
Undelegating and then withdrawing moves your own S back to you across a waiting period. Nothing was sold, so the two steps are transfers rather than trades.
Read-only by design.
- Kryptos only ever needs your public wallet address
- A public address is read-only. It can't move or spend anything
- We never ask for your recovery phrase or private key
- Remove a wallet whenever you like, and its data goes with it
If something doesn't sync.
Check whether anything stayed on Fantom Opera. It is still a live network with its own balances, and it needs adding as a separate wallet.
That is expected if you claimed early. Part of an early claim is burned, so the wallet figure is lower than the allocation, and the wallet figure is the correct one.
Import the wallet or exchange account that held your FTM. The cost carries through the one-for-one upgrade.
Still stuck? Email support@kryptos.io or open live chat from the app.