Simulation-tested across 1.8M+ Simulated transactions

    The Rules Layer Between Regulation and the Transaction

    Centsless selects the governing cash-rounding rule, determines the authorized transaction action, and preserves the evidence behind the decision.

    Centsless is commercial software. We start with a paid, scoped pilot rather than a free trial, then move to recurring per-location subscriptions.

    POS and Merchant Portals Now Live

    Explore our demo dashboards to see how Centsless compliance infrastructure works from both the POS vendor and merchant perspective.

    POS Portal Merchant Portal
    Transaction-Aware Cash Rounding Infrastructure

    Decision and evidence architecture

    What applies, what happens, and what proves why

    These are complementary layers in the Centsless architecture, not separate commercial products. Federal and state authorities enter the same versioned rule-selection process.

    Decision Engine

    What should happen?

    • • Authority and rule version
    • • Jurisdiction and effective date
    • • Tender and transaction context
    • • Permitted or required action

    Evidence Engine

    Why did it happen, and can we prove it later?

    • • Rule and authority applied
    • • Covered amount and transaction basis
    • • Adjustment and cash settlement
    • • Decision timestamp and evidence context

    Execution and compliance

    Different layers in the same transaction flow

    Execution answers what happened. Compliance answers why it was allowed. A POS can record the adjustment while Centsless preserves the applicable rule behind it.

    What a rounding feature does

    • • Calculates the adjustment
    • • Applies the settlement change
    • • Records the final cash amount

    What Centsless adds

    • • Jurisdiction, authority, and effective date
    • • Rule version and provenance
    • • Tender conditions and transaction eligibility
    • • Covered amount logic and decision rationale
    • • Evidence context for later review

    The engine, stage by stage

    Context resolution, rule determination, decision execution, evidence

    Each transaction moves through four stages before a POS ever sees an outcome.

    01

    Context Resolution

    • • ZIP-level jurisdiction awareness
    • • Actor
    • • Direction
    • • Tender
    • • Transaction type
    • • Effective date
    • • Activation status

    02

    Rule Determination

    • • Governing authority
    • • Current rule version
    • • Applicability
    • • Exact-change conditions
    • • Exceptions

    03

    Decision Execution

    • • Deterministic outcome
    • • Exact amount
    • • Rounded amount, where applicable
    • • Noncash exclusion
    • • Delegation or context-required states

    04

    Evidence

    • • Authority citation
    • • Rule version
    • • Context snapshot
    • • Decision reason
    • • Timestamp
    • • Evidence record
    Architecture

    Keep the POS. Add the Rule Layer.

    A lightweight middleware layer that complements existing POS systems without disrupting payment flows.

    The enacted rounding method applied only when the governing rule calls for it
    No rounding applied to card or EBT tender
    EBT tender remains unrounded, as designed against 7 CFR 278.2(b)
    Refund reversal behavior exercised in the simulation harness
    Deterministic ledger integrity
    API-first, stateless processing architecture
    Three Modules

    How It Works

    Three coordinated modules for complete cash flow coverage.

    Total Rounding

    (Cash Out)

    After rule selection, the final cash amount follows the method prescribed by the applicable rule. The exact ledger total remains available for tax reporting.

    Tender Normalization

    (Cash In)

    After applicability is resolved, cash received follows the governing tender rule, including the rule's treatment of split-tender transactions.

    Refund Normalization

    (Cash Returned)

    Refund handling follows the applicable rule and original transaction context so the downstream cash action can be explained and reviewed.

    Record Properties

    What You Get

    Every transaction produces verifiable, consistent results.

    Deterministic Outcomes

    Same input always produces same output. No random variation, no discretionary judgment.

    Dual Totals on Every Receipt

    Exact ledger total and rounded cash total both shown. Full transparency for customer and auditor.

    Auditable Records

    Every rounding event is written to an append-only audit log that re-verifies end to end.

    Neutrality Across Cash Flows

    Consistent rules for cash out, cash in, and cash returned. No bias toward merchant or customer.

    Rule-to-Action Flow

    Transaction context becomes an applicable rule, a decision, a POS action, and reviewable evidence.

    Transaction

    POS submits context

    Context

    Jurisdiction, tender, transaction, date

    Applicable Rule

    Authority, version, effective date

    Decision

    Allowed or required action

    POS Action

    Execution by the transaction system

    Authority
    Evidence
    Modules

    Three Modules. One Engine.

    Each module performs a distinct normalization function, producing verifiable outputs with full audit trail.

    Amount Due

    Total Rounding

    Ledger Normalization

    Applies deterministic rounding on the final transaction total for cash settlement.

    Cash Received

    Tender Normalization

    Input Normalization

    Normalizes incoming cash amounts to the nearest valid settlement unit.

    Refunds

    Refund Normalization

    Output Normalization

    Normalizes outgoing cash refund amounts for symmetry and auditability.

    Transaction Processing Stages

    Each cash transaction passes through three deterministic stages, producing verifiable outputs at each step.

    Amount Due

    Total Rounding

    1

    Cash Received

    Tender Normalization

    2

    Refunds / Cash Out

    Refund Normalization

    3
    All steps are jurisdiction-aware and audit-logged.
    Verification

    Proof and Transparency

    Every transaction produces verifiable, audit-ready records.

    Dual-Total Receipts

    Both exact and rounded amounts displayed on every receipt

    Deterministic Outcomes

    Same inputs always produce the same outputs, verifiable by any party

    Jurisdiction Snapshots

    Tax rates and rounding rules captured at transaction time

    Audit Re-verification

    Append-only audit records re-verified end to end

    How we validate the engine

    Before any pilot, the engine runs against public transaction datasets in a full simulation harness, every rounding decision checked against the statutory method for its jurisdiction.

    1.8M+

    Transactions exercised by the simulation harness

    46

    Public datasets in the harness

    11

    Execution modules exercised

    427,392

    EBT transactions exercised without rounding in the harness

    121,067

    Cash transactions rounded in the harness

    100%

    Harness decisions matching the encoded statutory method

    Integration

    Designed for POS Integration

    Centsless operates alongside existing POS logic as a lightweight rule layer. It does not replace the POS, modify digital payment totals, or alter primary ledger records, and it supports refund reversibility. Integration is API-driven and compatible with modern POS architectures.

    No database lock-in
    No tender interference
    Reversible transaction logic
    Merchant-safe deployment model

    Ready to Integrate?

    Get in touch to learn how Centsless integrates with your platform.

    Or read the requirements first: cash rounding compliance.

    v3.2 simulation harness | 1.8M+ transactions exercised | Multi-dataset simulation completed Q1 2026