Modern Treasury provides API for Payments & Banking

Modern Treasury API — Complete Guide to Payment Operations & Reconciliation in the USA

What Is the Modern Treasury API?

The Modern Treasury API is an enterprise-grade, REST-based financial infrastructure platform that enables businesses in the USA to automate payment operations, manage multi-rail money movement, and reconcile transactions in real time. Designed to help teams launch payment operations in days rather than months, the Modern Treasury API offers a single interface for multi-rail payments, programmable accounts, real-time reporting, and built-in compliance. Modern Treasury

Built as one API covering ACH, wires, real-time payments, and checks, the platform delivers ledgering, reconciliation, and orchestration as first-class primitives — not as black-box abstractions. Modern Treasury Whether you are a fintech startup, marketplace, B2B SaaS company, or enterprise treasury team, the Modern Treasury API provides the foundational infrastructure to move, track, and reconcile money at scale.

Official Website: moderntreasury.com API Documentation: docs.moderntreasury.com

Why US Businesses Are Adopting the Modern Treasury API

Payment initiation, status tracking, and reconciliation can be significantly automated through APIs, reducing manual intervention, minimizing the risk of errors and fraud, and accelerating payment cycles. The Global Treasurer

For US companies operating at scale, the Modern Treasury API solves three core challenges:

1. Fragmented Banking Relationships — Most companies connect to multiple banks using custom integrations. Modern Treasury offers a unified layer so teams manage all bank relationships through a single API and dashboard.

2. Manual Reconciliation Overhead — Finance teams spend enormous time matching payments to bank transactions. Modern Treasury's AI-powered reconciliation engine is designed to help teams reach $0 variance and achieve 100% reconciliation every day via exception handling and reconciliation rules.

3. Slow Payment Infrastructure — Bank onboarding alone can take months, and card-first payment service providers are expensive and slow to settle. Modern Treasury The Modern Treasury API eliminates these bottlenecks.

Core Features of the Modern Treasury API

1. Multi-Rail Payment Operations

Send and receive payments with ACH, Wire, Check, and more. Build high-volume payment flows using the API or initiate one-off payments by hand in the web dashboard. Modern Treasury

2. Real-Time Payment Rails (FedNow & RTP)

Modern Treasury's API connects financial institutions to the FedNow Service, allowing users to initiate real-time transactions, receive immediate alerts about payment statuses, and begin payment requests directly from customers to provide instant payments and better customer experiences. Modern Treasury

3. AI-Powered Reconciliation

Modern Treasury generates reconciliation rules using a combination of heuristics, deterministic algorithms, and large language models (LLMs). Pattern recognition within a company's dataset enables faster automation, achieving item-level reconciliation rates of 90–100%. Modern Treasury

4. Virtual Accounts & Programmable Ledgers

Create sub-accounts and ledger accounts programmatically to track balances, fund flows, and financial positions across entities — all through the API.

5. Approval Workflows & Audit Trails

Initiate, approve, and release payments with custom rules and access controls, and maintain an audit trail of all interactions with automatic activity logging. Silicon Valley Bank

6. General Ledger Sync

Eliminate long close cycles by instantly syncing reconciled payments to your General Ledger using pre-built integrations with accounting systems. Silicon

Modern Treasury API — Payment Methods Comparison

Modern Treasury API — Technical Integration Guide

Authentication

The Modern Treasury API uses HTTP Basic Auth. Your Organization ID acts as the username and your API key as the password.

curl https://app.moderntreasury.com/api/payment_orders \
  -u your_organization_id:your_api_key

Creating a Payment Order (ACH Transfer)

const fetch = require('node-fetch');

const response = await fetch('https://app.moderntreasury.com/api/payment_orders', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'Authorization': 'Basic ' + Buffer.from('ORG_ID:API_KEY').toString('base64')
  },
  body: JSON.stringify({
    type: 'ach',
    direction: 'credit',
    amount: 500000, // Amount in cents ($5,000.00)
    currency: 'USD',
    originating_account_id: 'your_internal_account_id',
    receiving_account: {
      account_type: 'checking',
      account_number: '123456789',
      routing_number: '021000021',
      name: 'Acme Corp'
    },
    metadata: {
      memo: 'Invoice Payment - Q1 2026'
    }
  })
});

const paymentOrder = await response.json();
console.log('Payment Created:', paymentOrder.id);

Fetching a Transaction (Reconciliation Check)

const transactionId = 'txn_abc123';

const response = await fetch(
  `https://app.moderntreasury.com/api/transactions/${transactionId}`,
  {
    method: 'GET',
    headers: {
      'Authorization': 'Basic ' + Buffer.from('ORG_ID:API_KEY').toString('base64')
    }
  }
);

const transaction = await response.json();
console.log('Transaction Status:', transaction.reconciled);
console.log('Amount:', transaction.amount, transaction.currency);

Listening for Webhook Events

const express = require('express');
const app = express();
app.use(express.json());

app.post('/webhooks/modern-treasury', (req, res) => {
  const event = req.body;

  switch (event.event_name) {
    case 'payment_order.completed':
      console.log('Payment completed:', event.data.id);
      break;
    case 'transaction.created':
      console.log('New transaction received:', event.data.id);
      break;
    case 'payment_order.failed':
      console.log('Payment failed:', event.data.id);
      // Trigger alert or retry logic
      break;
    default:
      console.log('Unhandled event:', event.event_name);
  }

  res.status(200).send({ received: true });
});

app.listen(3000, () => console.log('Webhook listener running on port 3000'));

Creating a Ledger Account (Virtual Accounts)

const response = await fetch('https://app.moderntreasury.com/api/ledger_accounts', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'Authorization': 'Basic ' + Buffer.from('ORG_ID:API_KEY').toString('base64')
  },
  body: JSON.stringify({
    name: 'Customer Wallet - John Doe',
    currency: 'USD',
    ledger_id: 'your_ledger_id',
    normal_balance: 'credit',
    metadata: {
      customer_id: 'cust_001',
      account_type: 'user_wallet'
    }
  })
});

const ledgerAccount = await response.json();
console.log('Ledger Account Created:', ledgerAccount.id);

Modern Treasury API — Key Webhook Events Reference

Who Should Use the Modern Treasury API in the USA?

Modern Treasury API vs. Alternatives — Comparison

FAQ

Q1: What is the Modern Treasury API used for? 

The Modern Treasury API is used to automate payment operations including ACH transfers, wire payments, real-time payments (RTP/FedNow), and book transfers. It also provides virtual accounts, programmable ledgers, automated reconciliation, and compliance tooling — all through a single REST API.

Q2: Is Modern Treasury API suitable for small businesses in the USA? 

Modern Treasury is primarily designed for growth-stage and enterprise companies with significant payment volumes. Startups and mid-market companies in fintech, marketplaces, and SaaS verticals commonly adopt the platform. Pricing is customized based on payment volume and features used.

Q3: How does Modern Treasury API handle payment reconciliation? 

Modern Treasury's reconciliation system uses a combination of heuristics, deterministic algorithms, and LLMs to generate reconciliation rules and suggest matches, enabling item-level reconciliation rates of 90–100%. Modern Treasury Finance teams retain full control over accepting or editing suggestions.

Q4: Does the Modern Treasury API support FedNow and real-time payments? 

Yes. The FedNow Service operates 24 hours a day, 7 days a week, 365 days a year, with a credit transfer limit of $10 million per transaction. Modern Treasury Modern Treasury provides a pre-built API integration so businesses can connect to FedNow without building a custom integration from scratch.

Q5: How many banks does Modern Treasury connect to?

Modern Treasury offers 30+ direct bank integrations, unifying account access to one API and dashboard to centralize a business's financial data. Modern Treasury

Q6: What programming languages are supported by the Modern Treasury API?

 Modern Treasury offers official SDKs for Node.js, Python, Ruby, Java, Kotlin, and Go. The API is REST-based and can be consumed by any language capable of making HTTP requests.

Q7: How does Modern Treasury API differ from Stripe or Plaid? 

Modern Treasury is purpose-built for payment operations and treasury management — not card payments or data aggregation. It offers direct bank connectivity, multi-rail payments, programmable ledgers, and automated reconciliation under a single platform. Stripe focuses on card-first payments, and Plaid is primarily a read-only data aggregation layer.

Q8: Can Modern Treasury integrate with accounting systems and ERPs? 

Yes. Modern Treasury offers pre-built integrations with accounting systems, allowing reconciled payments to sync instantly to your General Ledger. Silicon Valley Bank The platform also supports in-app journal entry exports for ERP platforms.

Q9: What is the Modern Treasury RISE Engine? 

The RISE Engine (Relay, Integrate, Structure, Enhance) is the infrastructure powering Modern Treasury's reconciliation enhancements. It is designed to help finance teams reach $0 variance and 100% reconciliation daily through exception handling and automated matching rules. Modern Treasury

Q10: How do I get started integrating the Modern Treasury API?

You can begin by visiting the official API documentation, signing up for sandbox access, and testing payment flows in a non-production environment. FintegrationFS can assist your US-based team with a fully managed Modern Treasury API integration — from architecture to deployment.