Shipping notification email: tell customers it is on the way

A shipping notification replaces the "where is my order?" support ticket. Its job is to give a tracking link and a believable date.

When it fires

On the carrier or fulfilment event, usually "label scanned" or "shipment created", not when staff click "mark as shipped" in your admin and not when the label is merely printed.

Workflow

1. Your fulfilment system posts a shipment.created event with carrier and tracking number.
2. You build the tracking URL for that carrier.
3. You send the email once per shipment (an order can have several).
4. You store shipment.notified_at.

Implementation (Python 3)

import os
import requests

TRACKING_URLS = {
    "ups": "https://www.ups.com/track?tracknum={n}",
    "usps": "https://tools.usps.com/go/TrackConfirmAction?tLabels={n}",
}

def notify_shipped(shipment, order):
    if shipment.notified_at:
        return
    url = TRACKING_URLS[shipment.carrier].format(n=shipment.tracking_number)
    resp = requests.post(
        "https://api.inboxili.com/api/v1/transactional/send",
        headers={"Authorization": f"Bearer {os.environ['INBOXILI_API_KEY']}"},
        json={
            "to": order.email,
            "from_email": "orders@yourdomain.com",
            "from_name": "Acme Store",
            "subject": "Your order {{order_number}} has shipped",
            "html_body": '<p>Order {{order_number}} is on its way with {{carrier}}. Estimated delivery: {{eta}}.</p><p><a href="{{url}}">Track your package</a></p>',
            "text_body": f"Track your package: {url}",
            "template_data": {
                "order_number": order.number,
                "carrier": shipment.carrier.upper(),
                "eta": shipment.eta_display,
                "url": url,
            },
        },
        timeout=10,
    )
    resp.raise_for_status()
    shipment.mark_notified(resp.json()["message_id"])

Sample email

Subject: Your order 10482 has shipped Order 10482 is on its way with UPS. Estimated delivery: Oct 12. Track your package

Things that go wrong

• Wrong carrier URL pattern. Test each carrier's link format with a real tracking number.
• Optimistic dates. If you cannot estimate reliably, say "within 3 to 5 business days" rather than a specific day.
• Multiple shipments per order producing confusing duplicates. Say "1 of 2 packages" in the body.

Delivery events

delivered and bounced webhooks let you show email status in your admin order view, which cuts support time when a customer says they never got it.

Deliverability notes

Tracking links should point at the carrier or your own domain. Third-party redirect domains in transactional mail look suspicious.