---
title: "Reg Z — TILA Billing-Error Resolution (12 CFR 1026.13) — KYE Protocol™ coverage"
description: "Reg Z — TILA Billing-Error Resolution (12 CFR 1026.13) coverage by KYE Protocol™ — every requirement bijection-mapped to the KYE™ artefact that enforces it."
url: https://kyeprotocol.com/compliance/reg-z/
lang: en
source: "KYE Protocol"
---

> Reg Z — TILA Billing-Error Resolution (12 CFR 1026.13) coverage by KYE Protocol™ — every requirement bijection-mapped to the KYE™ artefact that enforces it.

Reg Z — TILA Billing-Error Resolution (12 CFR 1026.13)

# Reg Z — TILA Billing-Error Resolution (12 CFR 1026.13) — 100% of in-scope requirements covered.

4 requirements · 3 in scope (3 enforced) · 1 out-of-scope (outside KYE™’s authority layer). The 100% is weighted over the in-scope base.

**Source:** The Truth in Lending Act and Regulation Z (12 CFR Part 1026) govern billing-error resolution for credit accounts in the United States. §1026.13 requires a creditor to acknowledge a billing-error notice, investigate, correct the account or send a written explanation of why no error occurred, and refrain from adverse action while the dispute is pending. KYE Protocol™ governs whether a correction / credit / billing-error determination in the dispute flow may PROCEED — under a named owner's recorded authority, with the transaction evidence captured as evidence events at transaction time, with a signed Evidence Pack™, and a recorded contestable determination. KYE™ does not adjudicate whether a billing error in fact occurred, decide whether to fight a dispute, or do fraud scoring. · **License:** Regulation Z (12 CFR Part 1026) is a US government work in the public domain; the KYE™ registry paraphrases each requirement's intent and cites the official section identifier for mapping purposes only.

## By category

| Category | Reqs | Enforced | Designed | Advisory | Deferred | Coverage |
| --- | --- | --- | --- | --- | --- | --- |
| Named-authority on the account correction / credit action | 1 | 1 | 0 | 0 | 0 | **100%** |
| Billing-dispute evidence record captured at transaction time | 1 | 1 | 0 | 0 | 0 | **100%** |
| Contestability & written-explanation reconstruction | 1 | 1 | 0 | 0 | 0 | **100%** |
| Substantive billing-error adjudication on the merits | 1 | 0 | 0 | 0 | 0 | **0%** |

## Every requirement → the KYE™ artefact that enforces it

| ID | Title | Status | KYE™ enforcement |
| --- | --- | --- | --- |
| `reg-z.billing-error-resolution-record` | An account correction / credit in the billing-error flow proceeds only under a recorded named-authority decision | enforced | **audit\_events**: `kye.purpose.request.v1`, `kye.purpose.admissibility.v1`, `kye.evidence.decision_map.v1` **engines**: `internal`, `internal` **rule\_packs**: `kye:rule-pack:chargeback-evidence` **dictionaries**: `internal` **constitution\_refs**: `constitution/12-PURPOSE-PERMISSION.md` |
| `reg-z.billing-dispute-evidence-record` | The billing-dispute investigation rests on an evidence trail captured at transaction time | enforced | **audit\_events**: `kye.evidence.decision_map.v1`, `kye.evidence.pack.v1` **engines**: `internal` **rule\_packs**: `kye:rule-pack:chargeback-evidence` **constitution\_refs**: `constitution/13-RESILIENCE-LOOP.md` |
| `reg-z.billing-dispute-contestability` | Contestability & reconstruction of the billing-error determination and the written explanation | enforced | **audit\_events**: `kye.evidence.pack.v1`, `kye.replay.context_seal.v1`, `kye.replay.proof.v1` **engines**: `internal`, `internal` **rule\_packs**: `kye:rule-pack:chargeback-evidence` **constitution\_refs**: `constitution/13-RESILIENCE-LOOP.md`, `constitution/21-DELEGATED-AUDITABILITY.md` |
| `reg-z.substantive-billing-error-adjudication` | Substantive adjudication of whether a billing error in fact occurred | out-of-scope | _(no enforcement cited)_ |

Canonical KYE™ surfaces referenced on this page: [Evidence Pack™](https://kyeprotocol.com/evidence-pack/) · [KYE Protocol™](https://kyeprotocol.com/).