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Overview

An off-ramp converts cryptocurrency (USDC, USDT) into fiat currency (COP, MXN, USD). Users send crypto and receive local currency in their bank account.

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Complete Off-Ramp Flow

1

Create User & Bank Account

Set up user profile and destination bank account
2

Get Quotation

Request price quote for crypto→fiat conversion
3

Create Ramp

Execute ramp with quote ID
4

User Sends Crypto

User transfers USDC/USDT to provided address
5

Conversion

KillB converts crypto to fiat
6

Fiat Delivered

Local currency sent to user’s bank

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Implementation Example

const executeOffRamp = async (userId, bankAccountId, amount) => {
  try {
    // 1. Get quotation
    const quote = await fetch('/api/v2/quotations', {
      method: 'POST',
      headers: {
        'Authorization': `Bearer ${token}`,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        fromCurrency: 'USDC',
        toCurrency: 'COP',
        amount: amount,
        amountIsToCurrency: false,
        cashInMethod: 'POLYGON',
        cashOutMethod: 'PSE'
      })
    }).then(r => r.json());
    
    console.log(`You will receive: ${quote.toAmount} COP`);
    
    // 2. Create ramp
    const ramp = await fetch('/api/v2/ramps', {
      method: 'POST',
      headers: {
        'Authorization': `Bearer ${token}`,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        quotationId: quote.id,
        userId: userId,
        accountId: bankAccountId,
        externalId: `offramp-${Date.now()}`
      })
    }).then(r => r.json());
    
    // 3. Show deposit address to user
    const depositAddress = ramp.paymentInfo[0].address;
    const depositNetwork = ramp.paymentInfo[0].network;
    
    return {
      rampId: ramp.id,
      depositAddress: depositAddress,
      depositNetwork: depositNetwork,
      amountToSend: quote.fromAmount,
      willReceive: quote.toAmount
    };
    
  } catch (error) {
    console.error('Off-ramp failed:', error);
    throw error;
  }
};

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Crypto Deposit Instructions

After creating the ramp, show users where to send crypto: 
const showDepositInstructions = (ramp) => {
  const paymentInfo = ramp.paymentInfo[0];
  
  return (
    <div>
      <h3>Send {ramp.fromAmount} {ramp.fromCurrency}</h3>
      <p><strong>Network:</strong> {paymentInfo.network}</p>
      <p><strong>Address:</strong> {paymentInfo.address}</p>
      <QRCode value={paymentInfo.address} />
      
      <button onClick={() => copyToClipboard(paymentInfo.address)}>
        Copy Address
      </button>
      
      <p>After sending, your {ramp.toCurrency} will be deposited to your bank within 1-3 hours.</p>
    </div>
  );
};

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Bank Account Setup

Create bank account for receiving fiat: 
{
  "type": "PSE",
  "userId": "user-id",
  "data": {
    "firstName": "Juan",
    "lastName": "García",
    "accountNumber": "1234567890",
    "bankCode": "0001",
    "type": "savings",
    "countryCode": "CO",
    // ... other required fields
  }
}

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Monitoring Deposit

Wait for user’s crypto deposit: 
const waitForCryptoDeposit = async (rampId) => {
  return new Promise((resolve, reject) => {
    const interval = setInterval(async () => {
      const ramp = await getRamp(rampId);
      
      if (ramp.status === 'CASH_IN_COMPLETED') {
        console.log('Crypto received! Converting...');
        clearInterval(interval);
      }
      
      if (ramp.status === 'COMPLETED') {
        console.log('Fiat delivered to bank!');
        clearInterval(interval);
        resolve(ramp);
      }
      
      if (['FAILED', 'CANCELED'].includes(ramp.status)) {
        clearInterval(interval);
        reject(new Error(`Ramp ${ramp.status}`));
      }
    }, 15000); // Check every 15 seconds
  });
};

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Refund Instructions

Provide fallback address in case of issues: 
{
  "quotationId": "quote-id",
  "userId": "user-id",
  "accountId": "bank-id",
  "refundInstructions": {
    "network": "POLYGON",
    "address": "0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb",
    "asset": "USDC"
  }
}
If the off-ramp fails, crypto will be refunded to this address.

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Next Steps

On-Ramp Guide

Implement fiat to crypto conversion

Status Tracking

Monitor ramp progress