Key takeaways
A POS integration API lets your point-of-sale system share sales, payment, stock, and customer data automatically with your other business tools.
Most integrations work on a simple request and response – the POS sends the sale amount to the terminal, and the terminal sends back approved or declined.
Airwallex brings online payments into an all-in-one financial platform, with POS Payments coming soon in Australia.
A POS integration API is a connection that lets your point-of-sale (POS) system exchange data automatically with your payment terminal, stock system, accounting software, and other business tools. Instead of staff re-keying sales into different places, every in-store transaction updates the systems that need it within seconds.
This guide explains how a POS integration API works step by step, shows real examples from Australian retail and hospitality, and compares the main types of POS integration.
What is a POS integration API?
A POS integration API is the link that lets your point-of-sale system share sales, payment, stock, and customer data with other software, without anyone entering it by hand. It's what turns a standalone till into an integrated POS.
A POS API integration runs in the background. Your team uses the same POS screen – the difference is what happens after they press "charge".
Without integration | With integration |
|---|---|
Each sale is recorded in the POS only | Sale data flows to connected systems automatically |
Stock levels are updated manually | Stock levels can update in near real time across connected in-store and online systems |
Payment data is exported and re-keyed into accounting software | Payment data flows into your connected accounting software |
Customer details sit in separate systems | Customer and loyalty data is shared between systems |
Higher risk of manual errors | Less data entry and fewer chances for mistakes |
For example, a customer buys a coffee and a pastry with Apple Pay. The POS records the sale, updates stock, sends the sale to Xero, and adds loyalty points with no re-keying.
What does "API" mean?
API stands for application programming interface: a set of rules that lets two pieces of software exchange data.
You don't need to code to understand it. What matters is which systems connect and what data flows between them – the same principle behind any payment API.
How does a POS integration API work?
A POS integration API works by sending small, structured messages (requests) from one system to another and receiving a response, usually in seconds.
Staff ring up the items on the POS.
In a common semi-integrated setup, the POS sends the transaction amount to the terminal or payment service through the integration.
The customer taps or inserts their card, or pays with a digital wallet.
The terminal securely sends the card data to the payment processor or acquirer for payment processing and approval.
The terminal returns approved or declined to the POS.
The POS completes the sale and pushes the data to your stock, accounting, and loyalty tools.
The POS only shares what's needed: the terminal gets the amount, not the basket, which keeps card data out of your POS. Integrations may also use webhooks – automatic notifications sent when something happens, like a new online order – so systems update in real time instead of checking constantly.
What data does a POS integration API share?
A POS integration API may share several types of data, depending on the systems and permissions you connect:
Transaction amount and currency: The total sent from the POS to the terminal.
Payment method and result: Card, eftpos, or digital wallet, and approved or declined.
Product and stock levels: What sold and what's left, across stores and online.
Customer and loyalty data: Who bought what, and points earned.
Orders (online and in-store): Click and collect, delivery, and table orders.
Settlement and refund data: Payouts, fees, and refunds to match against sales.
What flows depends on the systems you connect and your integration model.
What is a POS API integration example?
The most common POS API integration example is a POS connected to a payment terminal: the POS sends the sale amount, and the terminal returns the payment result.
Payment terminal integration
Your POS connects to your card machine, so staff never key in the sale amount. It's the foundation of integrated payments, and works with eftpos, Visa, Mastercard, Amex, Apple Pay, and Google Pay.
What flows: Sale amount out; payment result, method, and reference back.
Inventory and online store sync
An in-store sale can update inventory in a connected Shopify or WooCommerce store through an available integration, helping reduce overselling. With the right configuration, online orders can also appear in the POS for click and collect.
What flows: Product codes, stock levels, and online orders.
Accounting integration
Daily sales, fees, and payouts flow into Xero or QuickBooks for reconciliation. Payment providers may offer accounting and eCommerce integrations – a Xero integration, for example, can sync transactions automatically as bank feeds.
What flows: Sales totals, payment fees, refunds, and settlement payouts.
Loyalty and CRM
Every purchase automatically earns points and updates the customer's profile. Over time, you build one view of what each customer buys in-store and online.
What flows: Customer ID, purchase history, and points balance.
Hospitality ordering and delivery
Online, QR code table, and delivery app orders push straight into the POS and kitchen display. Staff no longer re-enter tablet orders, which cuts errors during the dinner rush.
What flows: Order items, table or delivery details, and payment status.
What are the main types of POS integration?
Common POS payment integration models include standalone terminals, semi-integrated terminals, cloud-connected integrations and SoftPOS or embedded SDKs. Each affects your PCI DSS scope differently – PCI DSS is the card-data security standard every business taking cards must follow.
Model | How it works | Development effort | PCI DSS scope | Best suited to |
|---|---|---|---|---|
Standalone terminal | Terminal runs separately; staff key in the amount | None | Varies by setup | Small, low-volume businesses |
Semi-integrated terminal | POS sends the amount; terminal handles card data and returns the result | Low | May be reduced | SME retail and hospitality |
Cloud-connected API | POS sends payment requests to the terminal over the internet; results link to orders | Medium | Varies by setup | Multi-location and omnichannel businesses |
SoftPOS / embedded SDK | Tap to pay on a compatible phone or tablet | Medium | May be reduced | Pop-ups, mobile checkout, kiosks, and platforms |
Standalone terminal
A standalone terminal processes payments separately, so sales and payment data don't connect. It needs no integration work and is often enough for a small, low-volume business.
Semi-integrated terminal
The POS can send the amount while a separate terminal handles card entry and returns the result. This may reduce the POS's exposure to card data, but PCI DSS scope depends on the solution, connected systems and implementation.
Cloud-connected API integration
This is what most people mean by a POS integration API: the POS sends a payment request through a connected service and receives a result that can be linked to the order. It can suit businesses that sell in-store and online, depending on the provider and setup.
SoftPOS and embedded SDK
SoftPOS turns a compatible smartphone or tablet into a payment terminal. An SDK (software development kit) lets developers build this into an app, kiosk, or platform.
What are the benefits of a POS integration API?
The main benefits of a POS integration API are less manual work, more accurate data, and a clearer view across every channel.
Less manual data entry and fewer errors: Sales flow into each system once, with no re-keying.
Real-time stock across channels: In-store and online inventory stay in sync, reducing overselling and stockouts.
Easier reconciliation: When payments are linked to orders, payouts can be easier to match.
Potentially reduced PCI DSS scope: Some validated integrations keep cardholder data out of the POS, but scope depends on the solution, connected systems and implementation.
One view of online and in-store customers: Purchase and loyalty data sit in one place.
The more systems you connect, the more these benefits add up.
What should Australian businesses look for in a POS integration?
Look for a POS integration that supports local payment methods, helps you understand PCI DSS scope, shows clear settlement data, supports data portability and connects online and in-store sales where needed.
Payment methods your customers use
Australian customers expect to pay with cards, eftpos, Apple Pay, and Google Pay, and many also want buy now, pay later (BNPL) at the counter. Check each works through your integration, not a separate device.
Ask your provider: "Which payment methods are supported natively through your POS integration?"
PCI DSS compliance scope
The future-dated requirements introduced in PCI DSS v4.0 became mandatory on 31 March 2025. Keeping cardholder data out of your POS may reduce the systems in scope, but it does not remove PCI DSS obligations.
Ask your provider: "What will my PCI DSS scope be with this integration, and which certifications does your platform hold?"
Reconciliation and settlement visibility
Look for itemised payouts that show the sales, fees, and refunds behind each deposit. A single lump-sum payment makes it harder to match settlements to your POS records.
Ask your provider: "Can I see a transaction-level breakdown of every payout?"
Data portability
Ask what transaction history and customer data you can export before switching providers. Stored card tokens used for saved-card and repeat payments may not be portable to a new processor.
Ask your provider: "What data can I export, and what happens to stored card tokens if I leave?"
Online and in-store on one platform
Using one platform for both channels can simplify reporting and reconciliation, but settlement structure and expansion requirements still depend on the provider and market.
Ask your provider: "Can I use the same platform and API for online and in-store payments?"
How Airwallex powers your customer payments
Airwallex brings your customer payments onto one global platform, with payments, settlements, and reporting in one place.
Australian businesses can use Airwallex Payments today to accept payments online – on a website, in an app, or through a payment link.
Accept 160+ payment methods, including major cards, Apple Pay, Google Pay, and local payment methods.
Integrate your way, with low-code Checkout, no-code Payment Links, Payment Plugins for platforms like Shopify and WooCommerce, or the full Payments API.
Settle like-for-like in 20+ currencies into your Airwallex Business Account so you can hold and pay out funds in the currency you were paid in.
Sync transactions with Xero, QuickBooks, and NetSuite for easier reconciliation.
POS Payments is coming soon in Australia, bringing in-store payments onto the same platform – including SoftPOS on compatible smartphones and tablets, and automatic order–payment linkage for easier reconciliation.
Frequently asked questions
What is a POS API integration example?
The most common POS API integration example is a POS connected to a payment terminal: the POS sends the sale amount, and the terminal returns approved or declined. Others include syncing stock with Shopify, sending sales to Xero, adding loyalty points, and pushing delivery orders to the kitchen.
What is POS API integration?
POS API integration is the connection that lets your point-of-sale system share data automatically with other software, such as your payment terminal, online store, and accounting tools. It keeps sales, stock, and payment records in sync without re-keying.
What is the difference between integrated and semi-integrated POS?
In a fully integrated POS, payment processing is built into the POS software, so card data can pass through your POS system. In a semi-integrated POS, the POS sends only the sale amount to a separate terminal, which handles card data and returns the result. Semi-integrated setups may reduce your PCI DSS scope.
Does a POS integration API affect PCI DSS compliance?
Yes. Your integration model affects which systems handle cardholder data and fall within PCI DSS scope. Semi-integrated and SoftPOS solutions may reduce the POS's exposure to cardholder data, but scope depends on the certified solution, device, connected systems and implementation.
Do I need a developer to integrate my POS?
Not always. Many POS systems offer ready-made integrations with terminals, accounting software, and eCommerce platforms that you switch on in settings. You'll usually need a developer for a cloud-connected API, an embedded SDK, or custom systems.
Sources
https://blog.pcisecuritystandards.org/now-is-the-time-for-organizations-to-adopt-the-future-dated-requirements-of-pci-dss-v4-x
This information doesn’t take into account your objectives, financial situation, or needs. If you are a customer of Airwallex Pty Ltd (AFSL No. 487221) read the Product Disclosure Statement (PDS) for the Direct Services available here.
Airwallex Editorial Team
Airwallex’s Editorial Team is a global collective of business finance and fintech writers based in Australia, Asia, North America, and Europe. With deep expertise spanning finance, technology, payments, startups, and SMEs, the team collaborates closely with experts, including the Airwallex Product team and industry leaders to produce this content.
- What is a POS integration API?
- How does a POS integration API work?
- What is a POS API integration example?
- What are the main types of POS integration?
- What are the benefits of a POS integration API?
- What should Australian businesses look for in a POS integration?
- How Airwallex powers your customer payments
