Square integrates two ways. On iOS and Android, the mobile app hands the charge to the Square app on the same device and returns when it is paid. Square Terminal connects the location to your Square account with OAuth and pairs a countertop terminal to each register with a device code.

Square is a current, fully supported integration with two distinct flavors, and the Credit Card Processor dropdown lists them separately:

• Square — for phones and tablets. The PHP Point Of Sale mobile app hands the charge to the Square Point of Sale app installed on the same iOS or Android device (with whatever Square reader is paired to it), then returns to the POS when the payment finishes.
• Square Terminal — for counters. The location connects to your Square account over OAuth, and each register pairs with its own Square Terminal device using a device code. No phone required.

If you are still comparing options, start with choosing a payment processor.

Square on iOS and Android (app handoff)

Set it up

1. Sign up as a merchant at squareup.com.
2. Install the Square Point of Sale app from the App Store or Google Play on the device you will sell from, sign in, and pair your Square reader in the Square app if you use one (contactless/chip reader or magstripe reader).
3. Install the PHP Point Of Sale app from the App Store or Google Play and sign in — see the mobile app.
4. In the POS, go to Locations, click Edit next to your location, and check Enable Credit Card Processing.
5. Set Credit Card Processor to Square.
6. If you charge in a currency other than US dollars, type its code into Currency Code (default USD).
7. Leave Multiplier to get total in cents at its default of 100 unless your currency does not use two decimal places — do not change it otherwise.
8. Click Submit.

Take a payment

1. Ring up the sale in the PHP Point Of Sale app and choose the Credit Card payment type.
2. Tap Process Credit Card. The device switches to the Square app with the exact amount.
3. Take the payment in Square — tap, chip, swipe, or keyed — and the device returns to the POS with the payment attached to the sale.

Because the handoff happens on the device, this flavor only works inside the mobile app on iOS or Android — not in a desktop browser.

Square Terminal (countertop device)

Connect the location to Square

1. Go to Locations, click Edit next to your location, and check Enable Credit Card Processing.
2. Set Credit Card Processor to Square Terminal.
3. Click Connect To Square and approve the authorization in the Square window that opens. Once connected, the button becomes Disconnect From Square for when you ever need to unlink the account.
4. Pick the matching store in the Square Location ID dropdown — Square accounts can hold several locations, and the sales must land in the right one.
5. Set Currency Code (default USD) and leave Multiplier to get total in cents at 100 unless your currency lacks two decimal places.
6. Click Submit.

Pair a terminal to each register

1. On the location form, find the register's row in the Registers table and click Get Square Device Code. A device code is generated for that register.
2. On the Square Terminal itself, choose to sign in with a device code and type the code. The terminal is now bound to that register.
3. To replace or remove the device later, click Unregister Terminal on the same row and pair again.

At sale time, choosing the Credit Card payment type pushes the exact amount to the register's paired terminal for tap, chip or swipe. Each register pairs with its own terminal.

Editing locations requires the Locations module permission on your employee account — see permissions and templates. Integrated processing also requires the POS to be served over HTTPS.

Settings reference

• Enable Credit Card Processing — master switch, off by default.
• Credit Card Processor — Square (mobile app handoff) or Square Terminal (countertop device).
• Currency Code — default USD; must match your Square account's currency.
• Multiplier to get total in cents — default 100; only change for currencies without two decimal places.
• Connect To Square / Disconnect From Square — the OAuth link between the location and your Square account (Square Terminal only).
• Square Location ID — which Square location receives the sales (Square Terminal only).
• Per register in the Registers table: Get Square Device Code / Unregister Terminal (Square Terminal only), and Enable Tips.

Common questions

Which option do I pick — Square or Square Terminal? Square if you sell from a phone or tablet with the Square app and a Square reader. Square Terminal if you have the standalone Square Terminal countertop device and want each register to drive its own.

Can I use the Square integration from a desktop browser? The app-handoff flavor cannot — it depends on switching to the Square app on the same mobile device. The Square Terminal flavor works from any browser, because the terminal is paired to the register over Square's cloud.

Payments go through but show under the wrong store in Square. Set the correct Square Location ID on the location form — that dropdown decides which of your Square locations receives the transactions.

I take payments in a currency other than US dollars. Type your currency's code into Currency Code. Leave the cents multiplier at 100 unless your currency genuinely has no two-decimal subdivision — changing it wrongly makes charges 100× off.

The device never comes back to the POS after the Square app takes over. Both apps must be installed and signed in on the same device, and the sale must be started from the PHP Point Of Sale app's Credit Card payment type. Update both apps if the handoff loops.

Do refunds go through the integration? Refund from the original sale in the POS so your reports stay right; card money movement follows Square's rules. See taking card payments and returns, exchanges and trade-ins.

Where do I see fees and deposits? In your Square Dashboard — Square remains the merchant of record for rates, fees and deposit timing. The POS records the tender for your own reports.