---
title: "Swift MT101 Coexistence Readiness Diff"
method: POST
path: "/v1/tools/check_mt101_coexistence_readiness"
tags: ["swift", "cbpr+", "mt101", "pain.001", "iso 20022", "coexistence", "compliance", "readiness"]
---

# Swift MT101 Coexistence Readiness Diff

`POST /v1/tools/check_mt101_coexistence_readiness`

## Request

- Base URL: `https://ainumbers.co`
- URL: `https://ainumbers.co/v1/tools/check_mt101_coexistence_readiness`
- Auth: none declared

Evaluates Swift CBPR+ MT101 message-type retirement readiness for the end of FI-to-FI coexistence, when bulk/multiple payment initiation drops MT101 (FIN) in favor of pain.001v9 (ISO 20022 MX). The former 14 November 2026 coexistence end was deferred by Swift on 27 August 2026 and no replacement date has been published, so the countdown below is planning-only against the superseded date. Declare the message format currently in production and a structural self-declared readiness checklist and get a deterministic ready/not-ready verdict plus days to the superseded planning date. Client-side, deterministic, zero PII.

**Tool URL:** https://ainumbers.co/tools/577-mt101-coexistence-readiness-diff.html
**AP2/Policy Mandate export:** yes

## Request body

- object
  - `currentMessageFormat` 'MT101' | 'pain.001v9', required: Message format currently in production for FI-to-FI bulk payment initiation
  - `asOfDate` string, required: ISO date (YYYY-MM-DD) to evaluate readiness as of
  - `emitsPain001v9Bulk` boolean: True if the sender's system already emits pain.001v9 for bulk FI-to-FI (only relevant when currentMessageFormat is pain.001v9)
  - `fallbackPathStaged` boolean: True if a fallback pain.001v9 path is staged (only relevant when currentMessageFormat is MT101)
  - `correspondentConfirmedReceipt` boolean: True if the correspondent has confirmed it can receive pain.001v9 (only relevant when currentMessageFormat is MT101)

## Response `200`

Successful tool execution result

- object
  - `mt101_coexistence_deadline` string
  - `days_to_deadline` number
  - `ready` boolean
  - `readiness_gaps` unknown[]
    - unknown
  - `structural_issues` unknown[]
    - unknown

---

[API](https://skmtc.dev/ainumbers/apis/ainumbers-co-fintech-intelligence-suite.md) · [All operations](https://skmtc.dev/ainumbers/apis/ainumbers-co-fintech-intelligence-suite/llms.txt) · [OpenAPI document](https://skmtc.dev/ainumbers/apis/ainumbers-co-fintech-intelligence-suite/revisions/b462e4f5bb28?raw)