Fix: Unwanted Shipping Emails & Duplicate Notifications

Troubleshoot customers receiving shipping notifications despite suppression, and duplicate confirmation emails from Shopify and ShipStation.

Customers Receiving Shipping Notifications Despite Suppression

What you're seeing: You have shipping notifications set to "Suppress" in your Send preset, but your customers or recipients are still getting shipping emails.

Why this happens: Send To Many suppresses Shopify's native notifications by setting the order contact email to a blackhole address (suppressed+{send_id}@sendtomany.com). Shopify respects this and sends its emails to that address instead of the customer.

However, other email services may use the customer's actual email address instead. Third-party tools like Klaviyo, Omnisend, or Mailchimp typically pull the customer's email from order.customer.email (the billing customer's actual email) rather than order.email (the order contact email where we put the suppressed address). Because the customer's real email is still on the order's customer record, the third-party tool sends the notification anyway.

How to fix it:

Add a filter or exclusion rule in your email tool to skip Send To Many orders. You can filter using any of these identifiers:

• Order tags: Every recipient order is tagged Send to Many #[Send ID], or another tag you've added to your order settings in Send To Many. Filter for orders where tags contain "Send to Many" or your custom tag.
• App attribution: Recipient orders have app = Send to Many in the order data.
• Contact email pattern: Orders with suppressed notifications have a contact email matching suppressed+*@sendtomany.com.

In Klaviyo, for example, you would add a flow filter that excludes orders where the order tag contains "Send to Many." The exact setup depends on your email platform, but the principle is the same: exclude orders that match any of the identifiers above.

Duplicate Shipping Notification Emails

What you're seeing: Recipients are getting two shipping confirmation emails: one from Shopify and one from ShipStation (or another fulfillment tool).

Why this happens: Both Shopify's built-in notifications and your fulfillment tool are configured to send shipping confirmations. When a shipment is created in ShipStation, it syncs back to Shopify, which triggers Shopify's own notification.

How to fix it:

Choose one of these two approaches:

• Suppress in Send To Many: Set your notification target to "Suppress" in your Send preset. This prevents Shopify from sending its own emails by replacing the order contact email with a blackhole address. ShipStation will still send to the customer email it has on file, so you get exactly one notification per shipment.
• Filter in ShipStation: Keep Shopify notifications enabled and instead add a filter in ShipStation to skip shipping confirmation emails for Send To Many orders. You can filter by the Send to Many order tag or by the send_to_many payment gateway.

See ShipStation Integration and Shipping Notifications.