---
title: "Nostro/Vostro A2A ROI Memo Generator"
method: POST
path: "/v1/tools/calculate_nostro_roi"
tags: ["nostro", "vostro", "ROI", "correspondent banking", "A2A", "treasury", "board memo"]
---

# Nostro/Vostro A2A ROI Memo Generator

`POST /v1/tools/calculate_nostro_roi`

## Request

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

Calculates the return on investment from migrating nostro/vostro correspondent relationships to A2A settlement rails. Models float reduction, fee savings, FX spread improvement, and operational cost reduction. Generates a board-ready ROI memo.

**Tool URL:** https://ainumbers.co/tools/19-nostro-roi-memo.html
**AP2/Policy Mandate export:** yes

## Request body

- object
  - `nostroBalance` number, required
  - `costOfFunds` number, required
  - `correspondentFees` number, required

## Response `200`

Successful tool execution result

- object
  - `total_annual_saving` number
  - `float_saving` number
  - `fee_saving` number
  - `fx_saving` number
  - `payback_months` number
  - `five_year_npv` number

---

[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)