WooCommerce Post-Purchase Emails

What this is for#

The window right after a WooCommerce purchase is the highest-engagement moment a customer ever has with you. Welcome them well and they convert again at 3-5× the baseline rate. Ignore them and you've left LTV on the table.

This guide walks the production setup: WooCommerce hook → AcelleMail list → automation flow. Pattern 2 from the WordPress + WooCommerce integration overview.

Prerequisites#

• A working WordPress + WooCommerce store
• A working AcelleMail install with an API token configured
• An AcelleMail list dedicated to post-purchase subscribers (separate from your general newsletter — different sequence, different opt-in semantics)
• An automation flow set up in AcelleMail to consume the events (we'll cover the template below)

Step 1 — The WooCommerce hook#

The right hook for post-purchase is woocommerce_order_status_completed — fires after payment AND fulfilment. NOT woocommerce_thankyou (fires on the thank-you page render even before payment confirms) or woocommerce_payment_complete (fires on payment but before fulfilment, can trip on subscriptions).

In a mu-plugin (per WordPress Subscriber Sync Step 2):

<?php
/**
 * Plugin Name: AcelleMail WooCommerce Post-Purchase
 * Description: Hook WooCommerce order completion to AcelleMail post-purchase list
 */

if (!defined('ACELLEMAIL_API_TOKEN') ||
    !defined('ACELLEMAIL_POST_PURCHASE_LIST_UID') ||
    !defined('ACELLEMAIL_BASE_URL')) {
    return;
}

add_action('woocommerce_order_status_completed', function ($order_id) {
    $order = wc_get_order($order_id);
    if (!$order) return;

    $email = $order->get_billing_email();
    if (!is_email($email)) return;

    // Build category tags for personalisation in the automation
    $tags = [];
    foreach ($order->get_items() as $item) {
        $cats = get_the_terms($item->get_product_id(), 'product_cat');
        if ($cats) foreach ($cats as $c) $tags[] = $c->slug;
    }
    $tags = array_unique($tags);

    // Pick the "headline" product (highest-value line item) for the email subject merge
    $headline_product = '';
    $top_subtotal = 0;
    foreach ($order->get_items() as $item) {
        if ($item->get_subtotal() > $top_subtotal) {
            $top_subtotal = $item->get_subtotal();
            $headline_product = $item->get_name();
        }
    }

    wp_remote_post(ACELLEMAIL_BASE_URL . '/api/v1/subscribers', [
        'headers' => [
            'Authorization' => 'Bearer ' . ACELLEMAIL_API_TOKEN,
            'Accept'        => 'application/json',
            'Content-Type'  => 'application/json',
        ],
        'body' => wp_json_encode([
            'MAIL_LIST_UID'   => ACELLEMAIL_POST_PURCHASE_LIST_UID,
            'EMAIL'           => $email,
            'FIRST_NAME'      => $order->get_billing_first_name(),
            'LAST_NAME'       => $order->get_billing_last_name(),
            'ORDER_ID'        => $order_id,
            'ORDER_TOTAL'     => $order->get_total(),
            'ORDER_CURRENCY'  => $order->get_currency(),
            'HEADLINE_PRODUCT' => $headline_product,
            'PRODUCT_CATEGORIES' => implode(',', $tags),
            'PURCHASE_DATE'   => $order->get_date_completed() ? $order->get_date_completed()->format('Y-m-d') : date('Y-m-d'),
        ]),
        'timeout'  => 10,
        'blocking' => false,
    ]);
});

Add the custom fields to the AcelleMail list (Lists → your post-purchase list → Fields → Add) before pushing — the API won't reject unknown fields, but they're discarded.

Step 2 — Set up the AcelleMail list#

In AcelleMail → Lists → New:

• Name: Customers (Post-Purchase)
• Default subject prefix: [Your Store]
• Custom fields:
  • ORDER_ID (number)
  • ORDER_TOTAL (decimal)
  • ORDER_CURRENCY (text, 3 chars)
  • HEADLINE_PRODUCT (text, 200 chars)
  • PRODUCT_CATEGORIES (text, 500 chars; comma-separated)
  • PURCHASE_DATE (date)
• Opt-in: Single (purchase IS implicit opt-in for transactional follow-up)

The reason to use a separate list (not your general newsletter): different cadence, different unsubscribe behaviour, different compliance status. A newsletter unsubscribe shouldn't stop post-purchase emails about an active order.

Step 3 — The 4-step automation sequence#

In AcelleMail → Automation → New Workflow on this list:

This is the proven 4-step template — see Post-Purchase Follow-Up Automation for the full content templates.

Personalising per product category#

Inside the automation, branch on PRODUCT_CATEGORIES:

• "If PRODUCT_CATEGORIES contains coffee" → use coffee-specific templates (related products, brewing tips)
• "If PRODUCT_CATEGORIES contains electronics" → use electronics templates (compatibility tips, warranty registration)
• Otherwise → use generic templates

Acelle's automation builder supports conditional branching — see the advanced triggers guide.

When the customer buys again#

If the customer makes a second purchase before completing the 4-step sequence, they're re-added to the list (Acelle handles as upsert) and the automation may re-evaluate. To prevent customers from getting "How's your X?" review-request emails for a product they bought last week, add an automation step: "If purchases in last 7 days > 1, skip" or use a re-entry cooldown.

Step 4 — Handle refunds / cancellations#

When an order is refunded, you may want to pause the automation for that customer (the day-7 review email feels off if they just got a refund):

add_action('woocommerce_order_status_refunded', function ($order_id) {
    $order = wc_get_order($order_id);
    if (!$order) return;

    // Remove from post-purchase list to stop the automation
    // First find subscriber by email:
    $find = wp_remote_get(
        ACELLEMAIL_BASE_URL . '/api/v1/subscribers/email/' . urlencode($order->get_billing_email()),
        ['headers' => ['Authorization' => 'Bearer ' . ACELLEMAIL_API_TOKEN, 'Accept' => 'application/json']]
    );
    $sub = json_decode(wp_remote_retrieve_body($find), true);
    if (!$sub || empty($sub['id'])) return;

    // Tag them as refunded (the automation can branch on this tag)
    wp_remote_post(
        ACELLEMAIL_BASE_URL . '/api/v1/subscribers/' . $sub['id'] . '/add-tag',
        [
            'headers' => ['Authorization' => 'Bearer ' . ACELLEMAIL_API_TOKEN, 'Accept' => 'application/json', 'Content-Type' => 'application/json'],
            'body' => wp_json_encode(['tag' => 'refunded:' . $order_id]),
        ]
    );
});

Then in the automation: "If tag = refunded, exit flow".

Common issues#

FAQ#

WooCommerce Subscriptions hooks? woocommerce_subscription_renewal_payment_complete fires on each renewal — add the same body to push to a subscriber-renewals list. Different sequence (skip "first review" since they already bought before; emphasize loyalty rewards).

WooCommerce Memberships hooks? wc_memberships_user_membership_status_changed — branch on $new_status to subscribe to relevant lists ("new member" vs "expired" vs "renewed").

Can I unsubscribe customers from the post-purchase list after Day 14? Add a final "Remove from list" step at the end of the automation. Or use a "Move to" step to add them to your general newsletter (they're now a paying customer; appropriate to nurture them long-term).

What about transactional emails (order confirmation, shipping notification)? Keep those in WooCommerce — that's its job, and they need to be 100% reliable per-order. The AcelleMail flow is for marketing follow-up.

Can I include the order line items in the welcome email? Yes — fetch $order->get_items() and pass them as a JSON-encoded LINE_ITEMS custom field, then parse in the AcelleMail template via merge tags + a small JS rendering. For most stores, just naming the HEADLINE_PRODUCT (the highest-value line) is enough.

How do I A/B test the post-purchase sequence? AcelleMail supports automation-level A/B (split subscribers 50/50, send different sequences). See A/B Testing Email Subject Lines for the principles.

Multilingual store? Pass the order's locale ($order->get_meta('_locale') if set, else get_locale()) as a custom field. Branch the automation on it to send the right-language sequence.

Related articles#

• Integrating AcelleMail with WordPress and WooCommerce — the master overview
• WordPress Subscriber Sync — sibling pattern for general user registration
• Post-Purchase Follow-Up Automation — the AcelleMail automation template that consumes these events
• Creating an Abandoned Cart Email Sequence — for pre-purchase WooCommerce events
• Advanced Automation Triggers and Conditions — for the conditional branching used in Step 3
• Getting Started with the AcelleMail REST API — API fundamentals
• REST API Authentication and Endpoints — subscriber + tag endpoints used in Step 4
• A/B Testing Email Subject Lines — optimise sequence performance
• Setting Up Queue Workers and Cron Jobs — automation depends on the queue