# Why can’t I send my entire ETH balance? An ordinary Ethereum transaction must cover both the ETH it sends and its gas cost. A wallet’s Max button therefore reserves a fee budget instead of sending the entire displayed balance. The final charge depends on actual gas use and the effective gas price, so a conservative fee allowance can leave a small remainder. Contract interactions may need more gas than a simple transfer. Evidence: [Ethereum gas and fees](https://ethereum.org/en/developers/docs/gas/) Canonical: https://degreesofsatoshi.com/encyclopedia/ethereum-send-max-balance/ Published: 2026-10-02 Substantively modified: 2026-10-02 Independently verified by an automated reviewer: 2026-10-02T19:27:58.939Z Data current through: 2026-10-02 AI-assisted research and drafting with a separate automated source-verification pass; no external expert or named human review is implied. ## Key facts - **Budget:** Transaction value and gas payment both require funds. ([Ethereum gas and fees](https://ethereum.org/en/developers/docs/gas/)) - **Unused gas:** Unused gas from the limit is not charged as if it were consumed. ([Ethereum gas and fees](https://ethereum.org/en/developers/docs/gas/)) - **Variable cost:** Contract execution can require more gas than a simple ETH transfer. ([Ethereum gas and fees](https://ethereum.org/en/developers/docs/gas/)) ## Max is a calculation with assumptions The wallet estimates the gas needed and chooses fee parameters. It must leave room for the transaction cost when calculating transferable ETH. A token balance cannot be substituted automatically for the ETH used by an ordinary mainnet transaction. A higher maximum fee can require a larger budget even when the effective price later turns out lower. Fee caps are limits, not promises that the full cap will be charged. Evidence: [Ethereum gas and fees](https://ethereum.org/en/developers/docs/gas/) ## Work through a simple transfer budget Assume a plain transfer uses 21,000 gas, the account has 0.1 ETH and the wallet budgets 30 gwei per gas. The budget is 21,000 × 30 billion wei = 0.00063 ETH, leaving 0.09937 ETH for value. These are hypothetical inputs, not a current fee quote. If the effective price is instead 20 gwei and gas use remains 21,000, the actual fee is 0.00042 ETH. Sending the budgeted value leaves 0.00021 ETH. Different execution or fee settings change the result. Evidence: [Ethereum gas and fees](https://ethereum.org/en/developers/docs/gas/) ## Do not force every transfer into the simple example A contract recipient, account behavior or application action can require a different gas estimate. Lowering the gas limit just to make a maximum amount fit can cause execution to run out of gas. Use the wallet’s supported estimate and review the recipient. An exact zero remainder is an interface objective, not a reason to discard the fee required for execution. Evidence: [Ethereum gas and fees](https://ethereum.org/en/developers/docs/gas/) ## Questions ### Is the leftover balance necessarily a wallet fee? No. It may be the difference between the reserved gas budget and the actual network charge. Check the transaction’s gas used and effective price. Evidence: [Ethereum gas and fees](https://ethereum.org/en/developers/docs/gas/); [Ethereum JSON-RPC API](https://ethereum.org/en/developers/docs/apis/json-rpc/) ### Can I send a token without holding any ETH? An ordinary mainnet transaction needs ETH for gas even when its value is a token transfer. Sponsored or other account-specific flows have separate rules. Evidence: [Ethereum gas and fees](https://ethereum.org/en/developers/docs/gas/) ## Claims and scope ### ethereum-send-max-balance-quick-answer An ordinary Ethereum transaction must cover both the ETH it sends and its gas cost. A wallet’s Max button therefore reserves a fee budget instead of sending the entire displayed balance. The final charge depends on actual gas use and the effective gas price, so a conservative fee allowance can leave a small remainder. Contract interactions may need more gas than a simple transfer. Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null} ### ethereum-send-max-balance-fact-budget Budget: Transaction value and gas payment both require funds. Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null} ### ethereum-send-max-balance-fact-unused-gas Unused gas: Unused gas from the limit is not charged as if it were consumed. Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null} ### ethereum-send-max-balance-fact-variable-cost Variable cost: Contract execution can require more gas than a simple ETH transfer. Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null} ## Sources - [Ethereum gas and fees](https://ethereum.org/en/developers/docs/gas/) — ethereum.org contributors. Gas budgeting, actual use, burnt base fee and proposer priority fees. Locator: Gas limit; fee calculation; base fee; priority fee. Retrieved: 2026-10-02T18:55:24.873Z. - [Ethereum JSON-RPC API](https://ethereum.org/en/developers/docs/apis/json-rpc/) — ethereum.org contributors. RPC requests explicitly identify addresses and block scope; receipts and removed log fields support verification examples. Locator: eth_getBalance; eth_getTransactionReceipt; block parameter; logs. Retrieved: 2026-10-02T18:55:24.990Z. ## Revision history - 2026-10-02: First publication after primary-source research and separate automated verification. ## Cite this entry Degrees of Satoshi editorial project. “Why can’t I send my entire ETH balance?.” Published 2026-10-02; updated 2026-10-02. https://degreesofsatoshi.com/encyclopedia/ethereum-send-max-balance/