Finance teams are under pressure to do more with less, more automation, more visibility, and tighter controls, without drowning in spreadsheets and manual approvals.
Enter expense management tools built on modern Card APIs.
Whether you’re building a SaaS tool for startups or creating an internal platform for your team, Card Issuing APIs give you the power to automate, track, and control spend in real time. And in regions like Latin America, where banking infrastructure can lag behind, the right card API can be a game-changer.
In this post, we’ll explore how to build expense tools using card APIs, what features matter most, and how platforms like Yativo simplify it with virtual prepaid cards powered by stablecoins.
Why Expense Management Is Broken
The traditional corporate card model comes with limitations:
- One card shared across multiple team members
- Manual expense reports and receipt matching
- Lack of real-time visibility or controls
- Delayed reimbursement cycles
- No easy way to scale or customize across teams or departments
Modern companies need programmable spend and that starts with card APIs.
What Is a Card API?
A Card API is a set of tools that allows developers to programmatically create, fund, manage, and monitor cards inside their own platform or app.
Key functions include:
- Creating virtual cards
- Setting spending limits or usage rules
- Funding cards dynamically
- Freezing, unfreezing, or canceling cards
- Fetching transaction data in real time
This lets you build a fully customized expense management solution that fits your organization or client’s workflow not the other way around.
Key Features for Expense Management
When building an expense tool using card APIs, look for:
✅ Instant Virtual Card Issuance
Let users create cards instantly per employee, department, project, or vendor.
✅ Spending Controls
Set transaction limits, allowed merchant types, or usage windows.
✅ Real-Time Transaction Monitoring
Stream transactions into dashboards or accounting tools as they happen.
✅ Integration Flexibility
Connect easily to payroll, accounting, ERP, or treasury platforms.
✅ Stablecoin Support
For global or LATAM-based teams, funding cards with USDC or USDT is faster and more efficient than relying on traditional banks.
Why Card APIs Empower Developers
Traditional reimbursement workflows are slow, manual, and prone to errors. Programmable card infrastructure lets you:
- Instantly issue cards via API
- Assign per-card rules and budgets
- Get real-time transaction visibility
- Automate reconciliation and compliance
All without negotiating with banks or purchasing cards in bulk.
Yativo Card API: Core Endpoints
Yativo provides a full suite of REST endpoints to manage virtual VISA cards, funded with stablecoins (USDC/USDT). Here’s how to use them.
1. Activate Customer for Card Creation
Before issuing cards, you must activate the customer.
Endpoint
swiftCopyEditPOST {{baseUrl}}/customer/virtual/cards/activate
Body Example (required customer data)
jsonCopyEdit{
"customerId": "123456789",
"customerEmail": "us**@*****le.com",
"idNumber": "A12345678",
"idType": "passport",
"firstName": "Jane",
"lastName": "Doe",
"dateOfBirth": "1990-01-01",
"phoneNumber": "+1234567890",
"city": "Santiago",
"state": "Santiago",
"country": "CHL",
"zipCode": "8320000",
"line1": "123 Elm St",
"houseNumber": "456",
"idImage": "https://..."
}
Response:
jsonCopyEdit{
"status": "success",
"message": "Virtual card service activated successfully.",
"activationDate": "2025-05-29T12:34:56Z"
}
This confirms the customer is approved for virtual card creation.
2. Create a Virtual Card
Once activated, issue a virtual prepaid VISA card.
Endpoint
swiftCopyEditPOST {{baseUrl}}/customer/virtual/cards/create
Body Example berkeleypayment.com+5developer.americanexpress.com+5docs.stripe.com+5:
jsonCopyEdit{
"customer_id": "123456789",
"amount": 500
}
Response:
jsonCopyEdit{
"status": "success",
"status_code": 200,
"message": "Virtual card created successfully",
"data": {
"id": "abcd1234",
"balance": 500,
"cardNumber": "40403818xxxx4628",
"last4": "4628",
"cardType": "virtual",
"cardBrand": "visa",
"cvv2": "849",
"expiry": "2027-05-29T00:00:00"
/* … */
}
}
Includes full card details like number, CVV, expiry, and billing info.
3. Top Up a Card
Add funds to a card from your stablecoin balance.
Endpoint
swiftCopyEditPOST {{baseUrl}}/customer/virtual/cards/topup
Body (assumed):
jsonCopyEdit{
"card_id": "abcd1234",
"amount": 200
}
Expect your platform to manage token-to-fiat and balance tracking accordingly.
4. Fetch Card Details
Retrieve card info and status.
Endpoint
swiftCopyEditGET {{baseUrl}}/customer/virtual/cards/{card_id}
Use this to confirm limits, display status, or print expiry dates in your interface.
5. Get Card Transactions
Fetch real-time transaction data.
Endpoint
bashCopyEditGET {{baseUrl}}/customer/virtual/cards/{card_id}/transactions
Receive details like merchant, amount, timestamp—essential for dashboards and reconciliation.
6. Freeze / Unfreeze Card
Control card usage programmatically.
Endpoint
bashCopyEditPATCH {{baseUrl}}/customer/virtual/cards/{card_id}/freeze
PATCH {{baseUrl}}/customer/virtual/cards/{card_id}/unfreeze
Useful when handling misuse, exceeding limits, or implementing one-time spree cards.
Example Integration Flow (Code Snippets)
In Node.js (using Axios):
jsCopyEditimport axios from 'axios';
async function activateUser(user) {
await axios.post(`/customer/virtual/cards/activate`, user, config);
}
async function createCard(customerId, amount) {
const res = await axios.post(`/customer/virtual/cards/create`, { customer_id: customerId, amount });
return res.data.data; // card info
}
async function topUpCard(cardId, amount) {
await axios.post(`/customer/virtual/cards/topup`, { card_id: cardId, amount });
}
async function fetchTransactions(cardId) {
const res = await axios.get(`/customer/virtual/cards/${cardId}/transactions`);
return res.data;
}
Why It Works for LATAM and Beyond
- Stablecoin-funding removes banking friction across borders
- Virtual cards, online-only aligns with mobile-first usage
- API-first control matches modern developer workflows
- Cashback in $TIVO tokens (from interchange) adds gamified incentives
- Compliance and KYC are pre-built into activation flows
Combine all this to launch expense, payroll, rewards, or IoT card tools in a matter of days.
Summary: Quick Endpoint Recap
| Function | Endpoint |
|---|---|
| Activate user | POST /customer/virtual/cards/activate |
| Issue card | POST /customer/virtual/cards/create |
| Top up card | POST /customer/virtual/cards/topup |
| Get card info | GET /customer/virtual/cards/{card_id} |
| List txns | GET /customer/virtual/cards/{card_id}/transactions |
| Freeze/unfreeze | PATCH /customer/virtual/cards/{card_id}/freeze & /unfreeze |
Wrapping Up
By integrating these Card APIs from Yativo, you can build a full-featured, automated expense management platform with virtual prepaid cards funded by stablecoins. Real-time data flows, strong control, and token-based rewards make it easy to offer a modern, developer-friendly experience.
👉 Explore Yativo Card Issuing API
👉 Get API keys and docs
Example Architecture
Here’s a simplified setup using Yativo’s Card API:
- User Onboards to Your App: KYC handled via embedded Yativo flow
- Create Virtual Card via API: Card issued instantly with your branding
- Set Controls: Limit to $500 USD, restrict to merchant category: SaaS or marketing
- Fund Card: Pull USDC from your Yativo USD balance and assign to card
- Monitor Transactions: Log activity in your app for reporting and real-time alerts
- Reward Users: Display $TIVO cashback earned each month
Use Cases
| Company Type | How It Uses Card APIs |
|---|---|
| Startups | Replace manual reimbursements with per-user cards |
| Agencies | Issue project-based cards for advertising spend |
| DAOs & Web3 Teams | Pay contributors with stablecoin-funded cards |
| Marketplaces | Give sellers expense cards linked to platform revenue |
| SMBs in LATAM | Manage team spending without dealing with local banks |