# Centsless API

## Docs

- [Query audit logs and verify hash chain integrity](https://docs.centsless.org/api-reference/compliance/audit-logs.md): Query immutable audit log entries by event type, user, or date range. Verify the full hash chain integrity before submitting compliance evidence to regulators.
- [POST /export — Export transactions as CSV](https://docs.centsless.org/api-reference/compliance/export.md): Export transaction data as a CSV file for regulatory reporting. Standard mode includes 53 fields. Filter by date range, payment method, and compliance status.
- [Merchant fraud risk profiles and platform overview](https://docs.centsless.org/api-reference/compliance/fraud.md): Retrieve per-merchant fraud risk profiles covering rounding ratios, override patterns, and void rates. View all merchants ranked by risk score to surface suspicious activity.
- [Compliance, audit, and fraud detection overview](https://docs.centsless.org/api-reference/compliance/overview.md): Every Centsless transaction produces a compliance status, fraud score, and audit hash. Use these endpoints to monitor patterns, detect abuse, and export regulatory evidence.
- [API error codes and responses](https://docs.centsless.org/api-reference/errors.md): The Centsless API returns standard HTTP status codes with a JSON body containing a machine-readable error code and a human-readable message. Learn what each status code means.
- [GET /jurisdictions — List all jurisdiction rules](https://docs.centsless.org/api-reference/jurisdiction/list.md): Returns all jurisdiction rules in the Centsless database including enacted, pending, and proposed legislation across all 50 states and territories.
- [GET /jurisdiction/{state} — Resolve by state or location](https://docs.centsless.org/api-reference/jurisdiction/resolve-state.md): Retrieve the rounding rule for a state, state+county, or state+county+city combination. Returns enforcement level, rounding mode, and legislation reference.
- [GET /jurisdiction/zip/{zip_code} — Resolve by ZIP](https://docs.centsless.org/api-reference/jurisdiction/resolve-zip.md): Look up any U.S. ZIP code to resolve rounding mode, enforcement level, and legislation reference. Returns the full city-county-state hierarchy. Covers 33,791 ZIP codes.
- [Centsless API reference overview](https://docs.centsless.org/api-reference/overview.md): The Centsless REST API base URL, authentication method, versioning, and rate limits. All endpoints accept JSON and return JSON except the CSV export endpoint.
- [POST /tip/validate-compliance — Tip credit validation](https://docs.centsless.org/api-reference/tipping/compliance.md): Check whether a merchant's hourly wage and average tips meet FLSA and state tip credit requirements. Pass the state, declared wage, and average tips per hour.
- [Create and distribute tip pools](https://docs.centsless.org/api-reference/tipping/pool.md): Aggregate tips across multiple transactions into a pool, then distribute them using equal, weighted, or hours-based methods. All pool operations are recorded in the audit trail.
- [Record tips, payouts, and wage theft analytics](https://docs.centsless.org/api-reference/tipping/process.md): Record cash and credit card tips, adjust tip amounts, process employee payouts, and retrieve tip analytics using the Centsless tipping API.
- [GET /transactions — Query and retrieve transactions](https://docs.centsless.org/api-reference/transactions/get.md): List transactions filtered by merchant, state, or type, with limit/offset pagination. Or fetch a single transaction by ID to retrieve its full detail record.
- [POST /transaction/override — Override rounding](https://docs.centsless.org/api-reference/transactions/override.md): Apply a manager-approved override to a transaction's rounding amount. Requires employee attribution and a reason code. Creates an immutable audit record.
- [POST /transaction — Process a cash transaction](https://docs.centsless.org/api-reference/transactions/process.md): Submit a cash transaction for jurisdiction-aware rounding. Pass merchant ID, amounts in cents, payment method, and a ZIP code or state. Returns rounded total and compliance status.
- [GET /transaction/{id}/receipt — Generate receipt](https://docs.centsless.org/api-reference/transactions/receipt.md): Generate a compliance receipt for a completed transaction. Use merchant format for customer receipts, audit for full records, or pos for minimal raw-cent POS output.
- [POST /transaction/refund — Process a refund](https://docs.centsless.org/api-reference/transactions/refund.md): Process a full or partial cash refund. The engine checks that the refund rounding delta correctly reverses the original transaction. Normalization failures are flagged, not blocking.
- [POST /transaction/void — Void a transaction](https://docs.centsless.org/api-reference/transactions/void.md): Cancel a transaction with a void reason and employee attribution. Creates a reversal record with negative amounts while maintaining hash chain integrity.
- [Authenticate with the Centsless API](https://docs.centsless.org/authentication.md): Authenticate with the x-api-key header on every request. Keys are role-scoped — merchant, auditor, or partner — with separate rate limits per environment.
- [Immutable audit trail and hash chain](https://docs.centsless.org/concepts/audit-trail.md): Every Centsless transaction is cryptographically hashed into a tamper-evident chain. Overrides, voids, and refunds are tracked with employee attribution and audit hashes.
- [EBT, card, and rounding exemptions](https://docs.centsless.org/concepts/ebt-and-exemptions.md): EBT/SNAP transactions are never rounded under 7 CFR 278.2 federal regulation. Card and mobile payments are also exempt from rounding regardless of jurisdiction.
- [Enacted cash rounding states and legislation](https://docs.centsless.org/concepts/enacted-states.md): Six U.S. states enacted cash rounding laws after penny production ended in 2025. Centsless covers all six with automatic jurisdiction resolution and compliance certification.
- [How jurisdiction resolution works](https://docs.centsless.org/concepts/jurisdiction-resolution.md): Centsless resolves the correct rounding rule for any U.S. location using a hierarchical cascade: city, county, state, then federal default.
- [Cash rounding methods supported by Centsless](https://docs.centsless.org/concepts/rounding-methods.md): Centsless applies the correct rounding method per jurisdiction automatically. Learn how Swedish, symmetrical, and other rounding modes work and which states use each method.
- [Export transaction data for compliance reporting](https://docs.centsless.org/guides/compliance-export.md): Use the Centsless export endpoint to generate a 53-field CSV covering the complete transaction lifecycle. Filter by date, payment method, and compliance status.
- [Handle overrides, voids, and refunds](https://docs.centsless.org/guides/overrides-voids-refunds.md): Manage post-transaction corrections using the Centsless API. Overrides adjust rounding, voids cancel transactions, and refunds reverse them — all with full audit attribution.
- [Integrate Centsless into your POS platform](https://docs.centsless.org/guides/pos-integration.md): A step-by-step guide to integrating the Centsless API into your POS platform. Covers onboarding merchants, processing transactions, and handling edge cases.
- [Process split tender transactions](https://docs.centsless.org/guides/split-tender.md): Split tender lets customers pay with multiple methods in one transaction. Centsless rounds only the cash portion and exempts EBT automatically per 7 CFR 278.2.
- [FLSA-compliant tip processing and pooling](https://docs.centsless.org/guides/tipping.md): Record cash and credit card tips, create and distribute tip pools, and validate state-specific tip credit compliance using the Centsless API.
- [Centsless API: Jurisdiction-Aware Cash Rounding](https://docs.centsless.org/introduction.md): Centsless provides real-time cash rounding compliance for all enacted U.S. states. POS vendors integrate once to cover every merchant on their platform.
- [Get started with Centsless in 5 minutes](https://docs.centsless.org/quickstart.md): Process your first cash transaction with Centsless using curl. Covers ZIP-based jurisdiction resolution, EBT exemption, and compliance receipt generation.