From Fantom to Sonic: A Practical Guide to Swapping FTM for S

The blockchain sector moves quickly. Technology that seemed advanced in 2020 can struggle with today’s expectations for low fees and high transaction capacity. Fantom (FTM), previously promoted as a high-speed smart contract platform, has now shifted to its next phase, Sonic (S).

This is not only a change of name or ticker. Sonic is a significant technical update to the network, focused on reducing data storage requirements, often referred to as “state bloat”. For FTM holders, this upgrade involves a token migration. Whether your tokens sit on an exchange or in a self-custody wallet, it is important to understand how the migration works, what your options are, and the risks involved.

Why did Fantom become Sonic?

To understand the migration, it helps to know what Sonic is designed to change. As blockchains grow, they collect large amounts of historical data. Every transaction, no matter how small, must be recorded and stored.

Over time, this can lead to storage bloat. On some networks, running a validator node, the computers that help secure and operate the chain, can require costly hardware with high storage capacity. If only well-funded operators can afford to run nodes, the network can become more centralised and potentially more fragile.

None of this guarantees that Sonic will succeed or achieve widespread adoption. It simply explains the stated motivation for the upgrade.

The solution: validator pruning

Sonic tackles the storage issue through a process called validator pruning. In simple terms, pruning allows a node to discard some older data that is no longer required to verify new transactions.

Instead of storing the full history of every transaction, a Sonic validator mainly keeps the current “world state”, which is a record of who owns what at the present moment, plus a relatively small number of recent blocks. This pruning happens continuously so the node can remain lighter while still processing new activity.

The Sonic team has reported that this design is intended to support more than 10,000 transactions per second. These are performance targets, not guarantees. Actual transaction speeds and fees will depend on wider network conditions, validator behaviour and user demand, and may be higher or lower than stated figures.

The migration: token swap details

The transition from FTM to S is a token swap in which the project replaces the old asset with a new one.

• Ratio: The swap occurs at a 1:1 ratio. For every 1 FTM you swap, you receive 1 S. This only refers to quantity, not price. The market value of each token can differ and can change at any time.
• Ticker: The new native token symbol on the Sonic network is S.
• Timeline: The migration began in late 2024. Two-way bridging between the old and new networks ended on 18 March 2025. Since then, migration is one-way only. You can convert FTM into S, but not S back into FTM using the official process.
• Current status: As of February 2026, the Sonic team states that the official swap portal remains open for holders who have not yet migrated. This could change in future. Always check Sonic’s official channels for the latest information.

If you do not migrate, you may be left holding a token with reduced utility or liquidity. This could make it harder or impossible to trade or use your FTM in future. There is also a risk that the project may close the swap portal at some point.

How to convert FTM to Sonic

Your migration route depends on where your FTM is currently held. In all cases, take care to avoid scams and double check any links you use.

Nothing in this section is a recommendation to swap. It is a general explanation of how the process works in practice.

1. For users on centralised exchanges

If your FTM was held on a major centralised exchange (CEX) during the migration period, the exchange may have handled the swap for you. Each exchange set its own rules and timelines.

CoinJar delisted Fantom (FTM) from both CoinJar and CoinJar Exchange in 2025. Customers were asked to withdraw their FTM to an external wallet where they could manage the migration to Sonic independently. CoinJar did not list Sonic after delisting FTM.

In many cases, exchanges paused FTM deposits and withdrawals, took a snapshot of user balances, then credited accounts with the equivalent number of S tokens once their own migration process completed. To see what happened in your case, check your account history and current balances to confirm whether your holdings are now listed as S rather than FTM.

If you still see FTM in your exchange account, or if your exchange has stated that it does not support the migration, you may need to:

• Review any announcements in the exchange’s help centre or blog.
• Consider withdrawing FTM to a compatible self-custody wallet if you intend to use the official swap portal.
• Factor in withdrawal fees and network conditions, which can change.

Holding assets on a centralised exchange carries its own set of risks, including counterparty and platform risk. If the exchange has operational issues, you may not be able to access your tokens, even if the underlying network is functioning normally.

2. For users with hot wallets (self-custody)

If you hold FTM in a self-custody wallet such as MetaMask, Trust Wallet, Phantom or a similar product, you are usually responsible for carrying out the swap yourself.

Always make sure that you control the private keys or recovery phrase to the wallet you are using. Never share your seed phrase or private keys with anyone.

Step by step guide

1. Find the official portal

   Go to the official Sonic Labs migration or swap portal. Only use links taken from Sonic’s official documentation, website, or verified social media profiles. Avoid using search engine ads, as these are often used by phishing sites that copy the look of the real portal.

2. Connect your wallet

   Click the connect button on the portal and choose your wallet provider. Confirm that your wallet is set to the Fantom Opera network or the network specified by the official instructions. If the site asks you to add or switch to a new network, read the details carefully before approving.

3. Approve the token access

   Your wallet will usually ask you to sign an “approve” transaction. This gives the migration smart contract permission to access your FTM tokens. Check that:

   • The contract address matches the one listed in official Sonic documentation.
   • The approval is limited to a sensible amount, not your entire wallet, wherever possible.

4. Swap your tokens

   Enter the amount of FTM you want to convert to S, then click the upgrade or swap button. Your wallet will ask you to sign a second transaction. You will need a small amount of FTM to pay network fees.

   Network fees can vary, so costs may be higher at busy times. If the transaction fails or is stuck, do not repeatedly sign new transactions without understanding why. This could increase your costs or expose you to scams.

5. Add the Sonic network and token

   After the swap, your FTM balance should decrease and your S balance should increase. You may need to:

   • Add the Sonic network details to your wallet if it is a different network from Fantom Opera.
   • Add the S token contract address so the balance is visible.

   Only use network and contract details from Sonic’s official channels. Adding the wrong token or network will not move your funds, but it can make it confusing to track where they are.

Self-custody gives you full control over your tokens, but also full responsibility. If you lose your seed phrase, send tokens to the wrong address, or interact with a malicious contract, there is usually no way to reverse the transaction or recover funds.

How it works in practice: the execution client

The Sonic upgrade changes how transactions are processed at a technical level. In the previous Fantom set-up, the execution client, the software that runs smart contracts and checks transactions, could become a bottleneck during times of heavy usage.

Sonic introduces a new execution environment that is designed to process many transactions in parallel. In theory, this should improve performance for users of decentralised exchanges (DEXs), lending platforms and other applications, especially during busy periods.

From a user’s point of view, migrating from FTM to S is like moving from the older engine to the newer one. The new design aims to separate the heavy storage tasks from the transaction processing. However, there is no guarantee that you will always experience faster or cheaper transactions. Actual results depend on how many users, validators and applications are active, and on how the code performs in real-world conditions.

Upgrades of this kind can also introduce new bugs or security issues. Even well audited code can contain flaws that only show up after launch, which could affect network reliability or asset safety.

Risks and red flags

Token migrations tend to attract fraudsters because they know users are actively searching for links and instructions. Staying cautious is essential.

• Fake migration portals

  Scammers often buy sponsored ads or use similar domain names to create fake versions of the migration portal. These websites can look almost identical to the real one. If you connect your wallet and sign their transactions, they may drain your funds.

  Always type the official website address directly or use trusted bookmarks. Do not rely solely on search engine results or social media replies.

• Unsolicited support messages

  No legitimate support team will contact you first in direct messages on platforms such as X (formerly Twitter), Discord or Telegram to offer help with migration or “account recovery”. These are usually social engineering attempts.

  If someone claims to be from Sonic, Fantom, an exchange, or from CoinJar, and asks for your seed phrase, private key or remote access to your device, treat this as a scam.

• Malicious contract approvals

  Be very careful when granting token approvals in your wallet. Some malicious websites ask for unlimited access to all tokens in your wallet, including stablecoins or unrelated assets.

  Before you sign, check which token and which amount the contract is requesting. If the requested permission seems too broad or unrelated to the migration, cancel the transaction. Use your wallet’s “revoke approvals” or a reputable approval-checking tool regularly to clean up old permissions.

In addition to scams, there are broader risks. Sonic is a relatively new version of the network, so there is technical, governance and adoption risk. Smart contracts can fail, validators can misbehave, and projects built on top of Sonic can be hacked or abandoned.

The future of Sonic

The move from Fantom to Sonic is more than a simple rebrand. It is a strategic attempt by the project team to keep the network competitive among newer, high-throughput blockchains by reducing storage demands and lowering the stated hardware requirements for validators.

By addressing state bloat and allowing more operators to run validator nodes with less storage, Sonic aims to support high-performance decentralised finance (DeFi) and other on-chain applications. These aims are not guaranteed. Success depends on developer interest, user adoption, security, regulation and wider market conditions.

For individual users, the immediate question is practical. Decide whether you want to keep exposure to this ecosystem, and if so, whether and how to migrate FTM to S in a secure way. If you do migrate, your tokens will exist on a newer network with a different technical design from Fantom Opera.

None of this guarantees that the value of S will rise, or even hold steady. Prices can be highly volatile and there is a real risk that your tokens could fall significantly in value or become worthless.