refund

The refund event tells GA4 to subtract revenue from a previously recorded purchase. It’s the counterpart to purchase — and just as critical for accurate revenue reporting. Without refund tracking, your GA4 revenue figures will exceed your actual revenue by every refund you’ve issued.

Refunds are unusual in one respect: they often happen server-side, initiated from your admin panel or payment processor, not from user action in the browser. For server-side refunds, you need the GA4 Measurement Protocol. For client-side refund confirmation pages, you can push to the dataLayer normally.

When to fire

Fire refund when:

• A user completes a refund request flow on the website (client-side — use dataLayer)
• An admin issues a refund in your order management system (server-side — use Measurement Protocol)
• A payment processor webhook confirms a refund (server-side — use Measurement Protocol)

Full refund — complete dataLayer push

// Full refund of a complete order
dataLayer.push({ ecommerce: null });

dataLayer.push({
  event: 'refund',
  ecommerce: {
    transaction_id: 'TXN-2024-98765',   // must match the original purchase transaction_id
    currency: 'USD',
    value: 142.97,                       // full order value being refunded
    tax: 28.59,
    shipping: 5.99,
    coupon: 'SUMMER15',
    items: [
      {
        item_id: 'SKU-001-BLK-L',
        item_name: 'Classic Leather Jacket',
        item_brand: 'Heritage Co.',
        item_category: 'Apparel',
        item_variant: 'Black / Large',
        price: 89.99,
        quantity: 1
      },
      {
        item_id: 'SKU-047-WHT-M',
        item_name: 'Cotton Crew T-Shirt',
        item_brand: 'Heritage Co.',
        item_category: 'Apparel',
        item_variant: 'White / Medium',
        price: 24.99,
        quantity: 2
      },
      {
        item_id: 'SKU-112-TAN-34',
        item_name: 'Woven Leather Belt',
        item_brand: 'Heritage Co.',
        item_category: 'Accessories',
        item_variant: 'Tan / 34',
        price: 34.50,
        quantity: 1
      }
    ]
  }
});

Partial refund — specific items only

For partial refunds where only some items are returned, include only the refunded items in the items array with the refunded quantities.

// Partial refund — only the jacket is being returned
dataLayer.push({ ecommerce: null });

dataLayer.push({
  event: 'refund',
  ecommerce: {
    transaction_id: 'TXN-2024-98765',   // same transaction ID as the original order
    currency: 'USD',
    value: 89.99,                        // only the refunded item's value
    items: [
      {
        item_id: 'SKU-001-BLK-L',
        item_name: 'Classic Leather Jacket',
        item_category: 'Apparel',
        price: 89.99,
        quantity: 1     // only 1 jacket is being refunded
      }
    ]
  }
});

Event schema

Event Schema refund

Parameter	Type	Required	Description
event	string	Required	Must be "refund"
ecommerce.transaction_id	string	Required	The transaction ID from the original purchase event. GA4 uses this to match and subtract from the purchase.
ecommerce.currency	string	Required	ISO 4217 currency code. Must match the original purchase currency.
ecommerce.value	number	Required	The monetary value being refunded. For partial refunds, this is only the refunded amount.
ecommerce.tax	number	Optional	Tax amount being refunded.
ecommerce.shipping	number	Optional	Shipping amount being refunded (if applicable).
ecommerce.coupon	string	Optional	Coupon code from the original order.
ecommerce.items[]	Array<Item>	Optional	Items being refunded. For a full refund, include all items. For partial refund, include only refunded items.
items[].item_id	string	Required	Must match the item_id from the original purchase.
items[].item_name	string	Required	Product name.
items[].price	number	Optional	Unit price at time of refund.
items[].quantity	number	Optional	Quantity being refunded.

Caution

The transaction_id in the refund event must exactly match the transaction_id from the original purchase event. GA4 uses this to attribute the refund to the correct purchase. If they don’t match, GA4 records the refund as an unmatched event and the revenue subtraction doesn’t work.

Server-side refunds via Measurement Protocol

Most refunds are not initiated by the user in a browser — they’re triggered by admins, webhooks, or automated systems. For these, use the GA4 Measurement Protocol to send the refund event directly to GA4 from your server.

// Node.js — server-side refund via GA4 Measurement Protocol
async function sendRefundToGA4(refundData) {
  const payload = {
    client_id: refundData.clientId,   // original buyer's GA4 client_id
    events: [{
      name: 'refund',
      params: {
        transaction_id: refundData.orderId,
        currency: refundData.currency,
        value: refundData.refundAmount,
        items: refundData.items.map(item => ({
          item_id: item.sku,
          item_name: item.name,
          price: item.price,
          quantity: item.refundQuantity
        }))
      }
    }]
  };

  const response = await fetch(
    `https://www.google-analytics.com/mp/collect?measurement_id=${GA4_MEASUREMENT_ID}&api_secret=${GA4_API_SECRET}`,
    {
      method: 'POST',
      body: JSON.stringify(payload)
    }
  );

  return response.ok;
}

Note

Server-side Measurement Protocol refunds require the original buyer’s client_id to properly attribute the refund. Store the GA4 client_id (the value of the _ga cookie) with each order at purchase time so you can include it when sending refund events from the server.

GTM configuration

For client-side refund flows (user-initiated refund confirmation pages):

1. Create a Custom Event trigger. Event name: refund. Name it CE - refund.

2. Create Data Layer Variables for ecommerce.transaction_id, ecommerce.currency, ecommerce.value, and ecommerce.items.

3. Create the GA4 Event tag. Event name: refund. Enable Send Ecommerce data. Add transaction_id, currency, and value as explicit event parameters.

4. Test by verifying in GA4 DebugView — refund events should appear with the correct transaction_id and value. Check GA4 revenue reports to confirm the amount is being subtracted.

Common mistakes

Wrong transaction_id. Using a new ID, a refund-specific ID, or any value other than the exact original purchase transaction_id means GA4 cannot match the refund to the purchase. Always use the original order ID.

Not tracking partial quantities. If a customer returns 1 of 2 T-shirts, the refund event should have quantity: 1 for that item, not quantity: 2. The quantity must match exactly what’s being refunded.

Sending refunds only from the frontend. Customer-initiated returns via a web portal can use the dataLayer. Admin-initiated refunds, payment processor webhooks, and automated refunds must go through the Measurement Protocol. Relying only on frontend tracking means every admin refund is invisible in GA4.

purchase The original purchase event that refund subtracts from.

Ecommerce Overview The full GA4 ecommerce event funnel.