TRC-20 The fungible token standard on Tron

TRC-20 is Tron’s fungible token standard, analogous to ERC-20 on Ethereum, and the backbone for most stablecoins, exchange tokens, and payment assets in the Tron ecosystem. With consistently low fees, instant finality, and a large retail user base, Tron has become a leading venue for day‑to‑day value transfer—especially for stablecoins—making TRC‑20 an essential primitive for both developers and users. This article explains how the standard works, what makes it different, and how to use it safely in 2025.

What is TRC-20?

TRC‑20 defines a minimal interface for fungible tokens on Tron Virtual Machine (TVM) compatible smart contracts. It specifies core functions like totalSupply, balanceOf, transfer, allowance, and transferFrom, along with standard events for transfers and approvals. The canonical specification is published as a TRON Improvement Proposal: TIP‑20: TRC‑20 Token Standard.

For developers, TRC‑20 feels familiar if you’ve built on Ethereum: Solidity is used to write contracts, and the TVM maintains compatibility with much of the EVM instruction set. You can learn more about TVM and the Tron developer stack in the official docs: Tron Virtual Machine.

Why TRC-20 matters now

• Stablecoin rail for payments: USDT issued natively on Tron is widely used for transfers and settlements due to speed and low costs. You can verify chain distribution on Tether’s transparency page: Tether Transparency.
• Cost model and throughput: Tron’s resource model (bandwidth and energy) keeps transaction costs predictable and typically low, which benefits small, frequent transfers. See details here: Tron Resource Model.
• User growth and activity: Tron has sustained high daily activity and token transfers; you can review near‑real‑time stats on TRONSCAN Analytics.

Note on market changes: Circle ended support for native USDC on Tron in 2024; teams and users should account for this when choosing stablecoin rails. Reference: USDC on TRON Network Ends (Circle).

How TRC-20 compares to ERC-20

• Interface parity: TRC‑20 mirrors ERC‑20 at the function/event level, making it easy to port contracts.
• Execution environment: TVM vs EVM—Tron’s TVM is Solidity‑compatible but not identical. Always test edge cases.
• Fees and resources: Tron replaces gas‑per‑transaction with bandwidth and energy. Users can stake TRX to obtain these resources or pay on demand. Developers should design UX with resource estimation in mind. See: Resource Model.

The developer’s path: from contract to mainnet

1. Design and implement your token contract.
2. Test locally in a TVM-compatible environment.
3. Deploy using TronWeb or similar SDKs.
4. Verify the contract on TRONSCAN and publish your metadata.
5. Build transfer, allowance, and admin workflows thoughtfully (mint/burn/owner roles) to mitigate risk.

Useful resources:

• TRON standard docs: TIP‑20
• SDK overview: TronWeb Introduction
• Contract verification: How to Verify a Contract on TRONSCAN
• Explore TRC‑20 tokens: TRONSCAN Token Directory

Minimal TRC-20 example (Solidity)

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

// Note: TVM is Solidity-compatible, but always test on Tron.
// This is a minimal example and omits advanced safety patterns.

contract ExampleTRC20 {
    string public name = "Example Token";
    string public symbol = "EXM";
    uint8 public decimals = 6; // Tron tokens often use 6 decimals
    uint256 public totalSupply;

    mapping(address => uint256) private _balance;
    mapping(address => mapping(address => uint256)) private _allowance;

    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);

    constructor(uint256 initialSupply) {
        _mint(msg.sender, initialSupply);
    }

    function balanceOf(address account) external view returns (uint256) {
        return _balance[account];
    }

    function transfer(address to, uint256 amount) external returns (bool) {
        _transfer(msg.sender, to, amount);
        return true;
    }

    function allowance(address owner, address spender) external view returns (uint256) {
        return _allowance[owner][spender];
    }

    function approve(address spender, uint256 amount) external returns (bool) {
        _allowance[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }

    function transferFrom(address from, address to, uint256 amount) external returns (bool) {
        uint256 allowed = _allowance[from][msg.sender];
        require(allowed >= amount, "Allowance exceeded");
        _allowance[from][msg.sender] = allowed - amount;
        _transfer(from, to, amount);
        return true;
    }

    // Optional mint/burn (be explicit about access control in production)
    function _mint(address to, uint256 amount) internal {
        totalSupply += amount;
        _balance[to] += amount;
        emit Transfer(address(0), to, amount);
    }

    function _burn(address from, uint256 amount) internal {
        require(_balance[from] >= amount, "Insufficient balance");
        _balance[from] -= amount;
        totalSupply -= amount;
        emit Transfer(from, address(0), amount);
    }

    function _transfer(address from, [address](https://onekey.so/blog/ecosystem/what-is-a-crypto-wallet-address/) to, uint256 amount) internal {
        require(_balance[from] >= amount, "Insufficient balance");
        require(to != [address](https://onekey.so/blog/ecosystem/what-is-a-crypto-wallet-address/)(0), "Invalid recipient");
        _balance[from] -= amount;
        _balance[to] += amount;
        emit Transfer(from, to, amount);
    }
}

Tips:

• Many Tron tokens choose 6 decimals for UX parity with USDT on Tron.
• If you implement privileged roles (owner, pauser, blacklist), document them publicly and consider on‑chain transparency via events.

Fees, bandwidth, and energy: what users actually pay

Tron’s model grants every account free bandwidth for small transfers and uses energy for contract execution. Users can:

• Stake TRX to gain bandwidth/energy, lowering ongoing costs.
• Pay per transaction when resources are insufficient.

For a deeper technical view, see the official guide: Tron Resource Model.

Developer UX implication: When sending TRC‑20 transfers from contracts (e.g., aggregators), account for the caller’s energy to avoid revert due to insufficient resources.

Stablecoins and payments on TRC-20

• USDT on Tron is among the most used stablecoin configurations for cross‑border transfers. Check issuance and reserves at Tether Transparency.
• USDC support on Tron ended per Circle’s policy update; consider alternatives for settlement flows: USDC on TRON Network Ends.

Design note: If your app depends on stablecoin mints/burns or compliance controls (e.g., freeze features), read the issuer’s documentation and contract code to understand potential admin actions and their effect on your users.

Interoperability and bridging

Many assets reach Tron via cross‑chain bridges or are issued natively as TRC‑20. If your product relies on bridging, understand:

• Trust model of the bridge (validators, oracles, upgradeability)
• Mint/burn mechanics or lock/unlock flows
• Exit/withdrawal liveness and fees

For Tron’s native bridge stack between Tron, Ethereum, and BNB Chain, review BitTorrent Chain (BTTC): BTTC Docs.

Security: common pitfalls and how to avoid them

• Approvals and phishing: Malicious dApps may request unlimited approvals. Encourage users to grant minimal allowances and periodically review them in their wallet or on TRONSCAN. A general directory is here: TRONSCAN TRC‑20 Tokens.
• Admin keys: If your TRC‑20 has mint, burn, pause, or blacklist, disclose the policy and use multi‑sig for key management. Multi‑signature is supported at the protocol level: Tron Multi‑Signature.
• Contract verification: Verify source code and match compiler settings so auditors and users can inspect the logic. Guide: Verify Contract on TRONSCAN.
• Resource failures: Transactions may fail if the sender lacks energy/bandwidth. Provide clear error surfaces and pre‑checks in your dApp.

Wallet experience and asset management

For users, the TRC‑20 experience should feel straightforward: the same Tron address receives TRX and tokens, and transfers confirm quickly. Still, protecting approvals, guarding seed phrases, and confirming token contract addresses are essential.

If you self‑custody significant TRC‑20 assets (e.g., USDT balances for settlement), a hardware wallet can materially reduce signing risk. OneKey secures private keys in a dedicated secure element, shows human‑readable transaction details on‑device, and supports Tron and TRC‑20 tokens natively—helpful when you need to scrutinize approval requests or verify recipient addresses before authorizing transfers.

Best practices checklist

For users:

• Verify the token contract on TRONSCAN before interacting.
• Test with a small transfer; then scale.
• Minimize token approvals and periodically clean them up.
• Consider staking TRX for energy if you transact frequently.

For developers:

• Keep the interface lean and predictable; avoid surprising token behaviors.
• Document any admin powers and publish a security policy.
• Verify contracts and publish audits where applicable.
• Monitor chain activity and fees; provide clear UX around resource usage.

Where to go next

• Standard and spec: TIP‑20: TRC‑20 Token Standard
• Developer docs: Tron VM and Resource Model
• Analytics: TRONSCAN Network Stats
• Stablecoin disclosures: Tether Transparency
• Cross‑chain: BTTC Docs

TRC‑20 has become a practical standard for global value transfer on Tron. Whether you are moving funds, building payment rails, or issuing your own asset, understanding the standard—and pairing it with secure key management—will set you up for success. For those holding meaningful balances, using a hardware wallet like OneKey to sign TRC‑20 transactions and approvals can harden your security without sacrificing speed on Tron.