# Email Invoice Gateway

The Email Invoice gateway allows you to send payment invoices to customers via email directly from WCPOS. This is perfect for situations where customers prefer to pay later or need to complete payment online using your web store's payment methods.

## Features[​](#features "Direct link to Features")

#### Email Integration

Send invoices directly from the POS interface

#### Customer Management

Auto-populate email from existing customer data or add new addresses

#### Online Payment

Customers receive a "Pay for this order" link to complete payment online

#### Flexible Workflow

Complete orders in-store or allow remote payment completion

## Installation[​](#installation "Direct link to Installation")

1

#### Install Email Invoice Gateway

Install from `WP Admin > POS > Settings > Extensions`, or download the latest **plugin zip asset** (not the GitHub source-code zip or tarball) from the [GitHub releases page](https://github.com/wcpos/email-invoice-gateway/releases) and upload it via `Plugins > Add New > Upload Plugin`.

2

#### Enable in WCPOS

1. Go to `WP Admin > POS > Settings > Checkout`
2. Find the **WCPOS Invoice Payment Gateway** in the list
3. Enable the gateway for use in the POS
4. Save your settings

note

This gateway doesn't require additional API keys or external service configuration. It uses your existing WordPress email system and WooCommerce payment methods.

## Usage[​](#usage "Direct link to Usage")

### Sending Invoices[​](#sending-invoices "Direct link to Sending Invoices")

1. **Add Items**: Add products to your cart in the POS

2. **Select Gateway**: Choose "Email Invoice" as the payment method

3. **Email Address**:

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   * For existing customers: Email is automatically populated from customer data
   * For guest orders: Enter the customer's email address manually

4. **Optional**: Check "Save to billing address" to update the customer's billing information

5. **Send Invoice**: Complete the process to send the invoice email

### Customer Experience[​](#customer-experience "Direct link to Customer Experience")

When you send an invoice, the customer receives an email containing:

* **Order Details**: Complete breakdown of items, quantities, and prices
* **Order Total**: Final amount due including taxes and fees
* **Payment Link**: Direct link to complete payment online
* **Order Information**: Order number and reference details

### Payment Completion[​](#payment-completion "Direct link to Payment Completion")

Customers can complete payment in two ways:

1. **Online Payment**: Click the "Pay for this order" link in the email
2. **In-Store Return**: Return to complete payment using other POS payment methods

The "Pay for this order" link takes customers to a dedicated payment page on your website where they can use any of your enabled web payment gateways (Stripe, PayPal, etc.).

## Email Management[​](#email-management "Direct link to Email Management")

### Existing Customers[​](#existing-customers "Direct link to Existing Customers")

* Email addresses are automatically retrieved from customer profiles
* Customer billing information is preserved
* Order history is maintained under the customer account

### Guest Customers[​](#guest-customers "Direct link to Guest Customers")

* Manually enter email addresses for one-time customers
* Option to save email to billing address for future reference
* Guest orders are properly tracked in WooCommerce

### Email Templates[​](#email-templates "Direct link to Email Templates")

The gateway uses WooCommerce's standard email templates:

* **Customisable**: Modify email appearance through WooCommerce email settings
* **Branded**: Include your store logo and branding
* **Professional**: Clean, professional invoice format
* **Mobile-Friendly**: Responsive design for all devices

## Use Cases[​](#use-cases "Direct link to Use Cases")

### Perfect For[​](#perfect-for "Direct link to Perfect For")

* **B2B Sales**: Business customers who need to process payments through their accounting systems
* **Large Orders**: High-value transactions that require approval or processing time
* **Remote Customers**: Customers who need to complete payment after leaving the store
* **Account Customers**: Regular customers with established payment terms
* **Quote-to-Order**: Converting quotes or estimates into payable invoices

### Workflow Examples[​](#workflow-examples "Direct link to Workflow Examples")

#### Retail Store

1. Customer selects items but needs to get approval for purchase
2. Send invoice email with all details
3. Customer completes payment online when ready
4. Order automatically updates in your system

#### Service Business

1. Complete service work and add items to POS
2. Send invoice to customer's accounting department
3. Customer pays online using preferred payment method
4. Receive payment confirmation and complete order

## Requirements[​](#requirements "Direct link to Requirements")

WCPOS

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: Pro version required for POS checkout

Email System

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: Working WordPress email configuration

Web Payment Gateways

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: At least one online payment method enabled in WooCommerce

SSL Certificate

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: HTTPS required for secure payment processing

## Troubleshooting[​](#troubleshooting "Direct link to Troubleshooting")

### Common Issues[​](#common-issues "Direct link to Common Issues")

Emails not sending

* Check WordPress email configuration
* Verify SMTP settings if using custom email service
* Test with WordPress email testing plugins
* Check spam folders for test emails

Payment links not working

* Ensure WooCommerce is properly configured
* Verify at least one payment gateway is enabled for web checkout
* Check that SSL certificate is properly installed
* Confirm order status allows payment

Customer can't complete payment

* Verify web payment gateways are active and configured
* Check that the order hasn't expired or been cancelled
* Ensure customer has sufficient payment method limits
* Test the payment process yourself

### Email Delivery[​](#email-delivery "Direct link to Email Delivery")

For reliable email delivery, consider:

* **SMTP Service**: Use services like SendGrid, Mailgun, or Amazon SES
* **Email Plugins**: Install WordPress SMTP plugins for better delivery
* **Domain Authentication**: Set up SPF, DKIM, and DMARC records
* **Monitoring**: Track email delivery and open rates

### Getting Help[​](#getting-help "Direct link to Getting Help")

For technical support:

* Visit the [GitHub repository](https://github.com/wcpos/email-invoice-gateway) to report issues
* Check WooCommerce email documentation for template customisation
* Test email functionality with WordPress email testing tools

## Screenshots[​](#screenshots "Direct link to Screenshots")

Screenshots will be added in a future update to show:

* Email address entry interface in the POS
* Professional invoice email template with order details
* Customer payment completion on the web store