# Permit signatures: authorizing token spending without an approval transaction

An ERC-2612 permit is a signed instruction that can set an ERC-20 allowance when submitted to a supporting token contract. It names an owner, spender, value, nonce and deadline within a signing domain. Signing does not itself transfer tokens, but an accepted permit can authorize later spending; other permit systems may use different rules.

Evidence: [Permit Extension for EIP-20 Signed Approvals](https://eips.ethereum.org/EIPS/eip-2612); [ERC-20 Token Standard](https://eips.ethereum.org/EIPS/eip-20)

Canonical: https://degreesofsatoshi.com/encyclopedia/permit-signatures/
Published: 2026-10-02
Substantively modified: 2026-10-02
Independently verified by an automated reviewer: 2026-10-02T18:12:41.505Z
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

- **Submission:** Any caller can submit a valid ERC-2612 permit; the owner’s signature supplies authorization. ([Permit Extension for EIP-20 Signed Approvals](https://eips.ethereum.org/EIPS/eip-2612))
- **Nonce:** Acceptance increments the owner’s permit nonce. ([Permit Extension for EIP-20 Signed Approvals](https://eips.ethereum.org/EIPS/eip-2612))
- **Deadline:** The deadline limits permit submission validity, not automatically the lifetime of the resulting allowance. ([Permit Extension for EIP-20 Signed Approvals](https://eips.ethereum.org/EIPS/eip-2612))

## A gasless signature can create a lasting permission

A valid permit sets the specified allowance. Afterward, the spender can use the token’s transferFrom behavior within that authorization, subject to token rules and balance.

The permit deadline is checked when permit is accepted. ERC-2612 does not turn the resulting allowance into an automatically expiring approval at that same time.

Evidence: [Permit Extension for EIP-20 Signed Approvals](https://eips.ethereum.org/EIPS/eip-2612); [ERC-20 Token Standard](https://eips.ethereum.org/EIPS/eip-20)

## Inspect the exact signed scope

Check the token and chain domain, spender, raw amount interpreted with the token’s decimals, nonce and deadline. A large numeric allowance can authorize much more than one intended swap.

Permit designs are not interchangeable. The ERC-2612 document describes differences from DAI-style permits, and other systems can authorize different actions. A wallet label saying “permit” does not identify all semantics.

Evidence: [Permit Extension for EIP-20 Signed Approvals](https://eips.ethereum.org/EIPS/eip-2612)

## Submission order can affect a workflow

Someone holding the signed message can submit it before the intended relayer. The allowance effect may be the same, but a later workflow that assumes the nonce is unused can fail.

An unsubmitted signature should be treated as an outstanding authorization while its conditions remain satisfiable. Rejecting a website popup afterward does not erase an already issued signature.

Evidence: [Permit Extension for EIP-20 Signed Approvals](https://eips.ethereum.org/EIPS/eip-2612)

## Questions

### Does a permit deadline revoke an allowance that was already created?

Not under ERC-2612 itself. The deadline controls whether the permit can be accepted; the resulting allowance follows the token’s allowance rules until changed or spent.

Evidence: [Permit Extension for EIP-20 Signed Approvals](https://eips.ethereum.org/EIPS/eip-2612); [ERC-20 Token Standard](https://eips.ethereum.org/EIPS/eip-20)

## Claims and scope

### permit-signatures-quick-answer

An ERC-2612 permit is a signed instruction that can set an ERC-20 allowance when submitted to a supporting token contract. It names an owner, spender, value, nonce and deadline within a signing domain. Signing does not itself transfer tokens, but an accepted permit can authorize later spending; other permit systems may use different rules.

Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null}

### permit-signatures-fact-submission

Submission: Any caller can submit a valid ERC-2612 permit; the owner’s signature supplies authorization.

Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null}

### permit-signatures-fact-nonce

Nonce: Acceptance increments the owner’s permit nonce.

Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null}

### permit-signatures-fact-deadline

Deadline: The deadline limits permit submission validity, not automatically the lifetime of the resulting allowance.

Scope: {"collection":"ethereum","dataAsOf":"2026-10-02","blockHeight":null}

## Sources

- [Permit Extension for EIP-20 Signed Approvals](https://eips.ethereum.org/EIPS/eip-2612) — Ethereum Improvement Proposals. Signed token allowances, deadlines, nonces and domain checks. Locator: Specification; Security Considerations. Retrieved: 2026-10-02T17:03:42.295Z.
- [ERC-20 Token Standard](https://eips.ethereum.org/EIPS/eip-20) — Ethereum Improvement Proposals. Token supply, displayed units and balance accounting. Locator: totalSupply; balanceOf; transfer; decimals; approve; allowance; transferFrom; Transfer. Retrieved: 2026-10-02T17:03:45.826Z.

## Revision history

- 2026-10-02: First publication after primary-source research and independent automated verification.

## Cite this entry

Degrees of Satoshi editorial project. “Permit signatures: authorizing token spending without an approval transaction.” Published 2026-10-02; updated 2026-10-02. https://degreesofsatoshi.com/encyclopedia/permit-signatures/