Integrating your cash drawer with the Square point-of-sale system ensures seamless cash management during transactions. To begin, confirm compatibility and gather the necessary hardware for a successful connection.

  • Receipt Printer: Required as an intermediary for cash drawer activation.
  • Interface Cable: RJ11 or RJ12 cable connects the drawer to the printer.
  • Supported Cash Drawer: Must work with Square-compatible receipt printers.

Note: Cash drawers do not connect directly to the Square reader or tablet. They must be linked through a compatible receipt printer.

Follow this sequence to physically set up your hardware:

  1. Connect the cash drawer’s cable to the receipt printer’s designated port.
  2. Plug the printer into a power source and link it to your tablet via USB, Ethernet, or Bluetooth, depending on the model.
  3. Turn on the printer and open the Square POS app to configure printer settings.
Component Connection Type Required
Cash Drawer RJ11/RJ12 to Printer Yes
Receipt Printer USB/Bluetooth/Ethernet Yes
Tablet/Phone Direct to Printer Yes

Checking Square-Compatible Cash Drawer Models

Before connecting any cash drawer to your Square point-of-sale system, it's essential to verify that the drawer model works seamlessly with Square hardware. Compatibility depends on both the drawer’s interface type and the receipt printer used. Most Square-compatible drawers operate through a printer-driven connection and require a specific cable configuration.

Choosing the correct model ensures proper functionality, including automatic opening upon transaction completion. Refer to the manufacturer’s documentation to confirm the cash drawer uses a standard RJ11/RJ12 interface and is triggered by a supported receipt printer like the Star Micronics TSP143 or Epson TM-T88V.

Recommended Models and Connection Types

Note: The cash drawer must connect directly to the receipt printer, not to the tablet or Square Stand.

  • Connection Type: RJ11/RJ12 cable (standard printer-driven connection)
  • Trigger Device: Supported receipt printer, not Square Reader or Stand
  • Power Source: No external power; powered via printer interface
Brand Model Compatible Printer Interface
APG Vasario 1616 Star TSP100, Epson TM series RJ11
Star Micronics CD3-1616 Star TSP143 RJ12
MMF VAL-u Line Epson TM-T88V RJ11
  1. Identify your receipt printer model used with Square.
  2. Select a cash drawer that uses the correct trigger cable (RJ11 or RJ12).
  3. Ensure the drawer is listed as compatible by both Square and the drawer manufacturer.

Identifying the Right Connection Ports on Your Hardware

Before establishing a reliable link between your cash drawer and the Square system, it's essential to understand the available physical connection points on both your drawer and compatible receipt printer. These ports serve specific roles and must match the interface supported by your hardware setup.

Most standard cash drawers do not connect directly to a tablet or Square Stand. Instead, they typically connect via a receipt printer acting as an intermediary. Identifying the correct port ensures the cash drawer receives the open signal when a transaction completes.

Common Port Types and Their Purpose

  • RJ-11/RJ-12 Port – Often labeled as “Drawer” or “DK”, this telephone-style connector is the most commonly used and links the drawer to the receipt printer.
  • USB Port – Some advanced cash drawers offer direct USB connections, typically used with specific USB-supported Square Stands.
  • Serial (RS-232) Port – Less common, but still in use for older or industrial-grade drawers.

Note: Do not confuse an RJ-11 cash drawer port with an Ethernet port–they may look similar but serve different functions and are not interchangeable.

Port Type Location Used With
RJ-11 / RJ-12 Back of receipt printer Standard cash drawers
USB-A / USB-B On Square Stand or drawer USB-compatible drawers
RS-232 Serial On drawer or external adapter Legacy systems
  1. Inspect the back of your receipt printer or Square hardware.
  2. Locate a port labeled “DK”, “Drawer”, or identify the USB input.
  3. Match it with your cash drawer’s cable connector.

Setting Up the Cash Drawer with Square Stand

To integrate your cash drawer with a Square Stand, the essential step is ensuring compatibility with a supported receipt printer. The drawer connects to the printer, not directly to the iPad or stand. When a transaction completes, the printer sends a signal to open the drawer.

This setup ensures secure, automated control over the cash drawer and prevents manual openings that are not tied to sales activity. Proper installation also helps maintain a seamless checkout experience for both staff and customers.

Steps to Connect the Drawer

  1. Connect the cash drawer to the receipt printer using the RJ11 cable.
  2. Plug the receipt printer into the Square Stand via USB.
  3. Ensure the Square Point of Sale app recognizes the printer in the settings.
  4. Enable automatic drawer opening for cash transactions.

Note: The cash drawer cannot connect directly to the Square Stand. It must be linked through a compatible receipt printer such as the Star Micronics TSP143.

  • Use a standard RJ11 connector cable (often included with the drawer).
  • Verify printer compatibility with Square hardware before purchase.
  • Check drawer functionality through a test print in the app settings.
Component Connection
Cash Drawer RJ11 to Printer
Receipt Printer USB to Square Stand
iPad Mounted on Square Stand

Configuring the Cash Drawer in the Square App

Before using your cash drawer with Square, it's essential to ensure that all hardware connections are properly established. The drawer must be linked to the receipt printer via the provided RJ11 cable. The Square app communicates with the drawer through this printer, allowing for automated opening when transactions are finalized.

Once all hardware is connected, configuration within the Square app is required. This step defines how and when the drawer opens–whether for every sale, only with cash payments, or manually.

Steps to Adjust Drawer Settings in the Square App

  1. Open the Square Point of Sale app on your device.
  2. Tap Settings, then select Hardware.
  3. Choose Printers and select the connected receipt printer.
  4. Enable the option labeled “Cash Drawer”.
  5. Select when the drawer should open (e.g., cash only, every payment).

Ensure your receipt printer is compatible with Square and is correctly recognized in the app; otherwise, drawer settings will not be accessible.

Option Description
Cash Payments Drawer opens automatically only when cash is received.
All Transactions Drawer opens for every type of payment.
Manual Only User opens drawer via in-app button when needed.
  • Use the test print option to confirm drawer functionality.
  • Keep the drawer key in a secure place in case manual opening is required.

Any changes to drawer settings apply only to the selected printer profile, so configure each connected device individually.

Pairing a Cash Drawer via Receipt Printer Connection

To integrate a cash drawer with your POS setup through a receipt printer, ensure that the printer supports a peripheral port compatible with your drawer. Most models use an RJ11 or RJ12 cable, which resembles a standard telephone connector. This method allows the drawer to open automatically after printing a receipt, streamlining the checkout process.

Begin by confirming that your receipt printer is connected and recognized by your POS terminal. Once verified, connect the cash drawer to the printer's dedicated port. The drawer's trigger mechanism depends entirely on commands from the printer, so no additional software configuration is typically required on the POS device itself.

Steps to Connect the Drawer

  1. Turn off the receipt printer before connecting the drawer.
  2. Insert the drawer's cable into the DK port on the back of the printer.
  3. Power the printer back on and run a test print to confirm connectivity.
  • Ensure the drawer uses a supported voltage (commonly 24V).
  • Check for a “click” sound from the drawer when triggered–it indicates successful pairing.

Important: Always use manufacturer-approved hardware. Mismatched voltages or unsupported drawer types may damage the printer or prevent the drawer from opening reliably.

Component Connection Type Function
Cash Drawer RJ11/RJ12 Cable Stores cash; opens on receipt signal
Receipt Printer Peripheral Port (DK) Sends open command to drawer

Troubleshooting When the Cash Drawer Fails to Open Automatically

When the till connected to your Square-compatible setup doesn't pop open after a transaction, it's often due to miscommunication between hardware components. This typically involves the printer, interface cable, or the drawer's internal trigger mechanism.

Resolving this issue requires a step-by-step check of connections and settings to isolate the cause. Below are the most common problem points and how to fix them effectively.

Steps to Diagnose and Fix the Issue

  1. Check Receipt Printer Configuration
    • Ensure the receipt printer is powered on and loaded with paper.
    • Confirm it is selected as the default printer in the Square app.
    • Verify that the "Open Cash Drawer" option is enabled under printer settings.
  2. Inspect Connection Cable
    • Use only the RJ11/RJ12 cable provided by the drawer manufacturer.
    • Make sure the cable is plugged into the correct port on the receipt printer labeled “DK” or “Drawer”.
  3. Test Hardware Manually
    • Open the drawer using the manual release to check for mechanical issues.
    • Attempt to print a test receipt and listen for the drawer’s trigger sound.
Component What to Verify
Receipt Printer Correct model, power supply, paper, Square integration
Interface Cable Secure connection, undamaged pins, correct type (RJ11/RJ12)
Cash Drawer Manual function, electronic trigger response

Tip: The drawer will not open if no receipt printer is detected. Make sure your printer is both compatible and actively linked to your Square setup.

Testing the Cash Drawer After Setup

Once the connection between your cash drawer and Square is established, it’s essential to perform a series of tests to ensure everything functions properly. This will help confirm that the drawer responds to commands from Square’s system and that the setup was successful. Proper testing avoids potential issues during real transactions and ensures a smooth experience for your business operations.

The following steps guide you through the testing process to verify the proper functioning of the cash drawer:

Steps to Test the Cash Drawer

  1. Open Square's Point of Sale app.
  2. Ensure the cash drawer is securely connected to the receipt printer (if applicable) or directly to the register.
  3. Try opening the drawer using the POS system by completing a test transaction.
  4. Ensure the drawer opens automatically when you complete the sale.

Important: If the drawer doesn’t open, verify the connection or check for any issues with the printer's settings.

Common Troubleshooting Tips

  • Check the cable connections to ensure they are properly secured.
  • Test the power supply to the cash drawer and printer, ensuring both are receiving adequate power.
  • Review the settings in the Square app to ensure the drawer is configured correctly.
  • If the drawer is not responding, try restarting both the POS system and the drawer.

Additional Information

If everything is functioning correctly, you should be able to complete sales and open the drawer as needed without any issues. If problems persist, consider contacting Square's support team for further assistance.

Using a Manual Key Override When Needed

In some situations, the automated connection between the Square system and the cash drawer may fail, making it necessary to manually open the drawer. This is where the manual key override comes into play. It allows you to open the cash drawer without relying on the electronic connection between the drawer and your point-of-sale (POS) system. It's important to know when and how to use this feature to prevent disruption in your sales process.

The manual key override is particularly useful in scenarios where the POS system is down, or there is a temporary malfunction in the electronic mechanism. In such cases, you can use the physical key to open the drawer and continue with your transaction processing. This method ensures you don't experience downtime during critical moments in your business operations.

How to Use the Manual Key Override

  • Locate the manual key slot on the cash drawer.
  • Insert the override key into the slot.
  • Turn the key in the direction indicated (usually clockwise) to unlock the drawer.
  • Open the drawer and complete your transaction as needed.

Important: Always keep the manual override key in a secure location to prevent unauthorized access to the drawer.

When to Use the Key Override

  1. When the cash drawer fails to open automatically due to a system malfunction.
  2. During hardware or software updates that temporarily disable electronic functions.
  3. If your POS system or network experiences an issue preventing communication with the drawer.

Key Override Maintenance

Action Recommended Frequency
Test the manual key mechanism Monthly
Clean the key and keyhole Every 3 months
Replace the key if lost or damaged As needed