A complete guide: Multiple GA4 Pixels

TagFly lets you connect more than one Google Analytics 4 (GA4) property to the same store. This guide explains how to add multiple GA4 properties, choose how each event is tracked, and avoid the most common pitfall — duplicated or split analytics data when several properties track the same domain.

What you will learn

• What are multiple GA4 pixels?
• How to add a GA4 property
• Choosing which events to track (server-side vs client-side)
• The other configuration tabs
• The "multiple GA4 properties" warning
• Common use cases
• Best practices

What are multiple GA4 pixels?

Previously, each store could connect only one GA4 property. Now you can add several — each with its own Measurement ID — and every property that is turned on receives the same set of events you choose to track.
This is useful when more than one GA4 property genuinely needs the same data: migrating from an old property to a new one, sending conversions to both a brand and an agency, or keeping a separate property for testing. Each property is configured independently in the ID & Events tab, and turning one on or off does not affect the others.

How to add a GA4 property

Open the TagFly Google Analytics settings and go to the ID & Events tab, then complete three steps:

1. Choose a Google account. Under Google account, select the connected Google account that this GA4 property belongs to. If the account you need isn't listed, connect it first.
2. Choose the property. Under Choose Property, select your Account, then the Property, then the Measurement ID (G-XXXXXXX). The Measurement ID is the exact destination that will receive your events.
3. Select your events. In the Events table, choose which eCommerce events to track and how to send each one (see the next section).

To add another property, repeat these steps with a different Measurement ID. Properties run in parallel and independently.

Choosing which events to track (server-side vs client-side)

The Events table lists each eCommerce event (Page View, View Item List, Select Item, Add to Cart, Begin Checkout, Purchase, and more) with two columns:

• Server-side — TagFly sends the event directly to GA4 through the Measurement Protocol. This is more reliable because it isn't blocked by ad blockers or browser privacy features (ITP).
• Client-side — the event fires from the shopper's browser through gtag. This preserves signals that are stronger when measured in the browser.

You can enable server-side, client-side, or both for each event. Some events have a fixed tracking type (shown as a greyed-out checkbox) — this is by design and can't be changed.

Tip: For critical events like Purchase, server-side tracking is recommended so you don't lose conversions to ad blockers. Avoid enabling both server-side and client-side for the same event to the same property unless deduplication is in place, or that property may count the event twice.

The other configuration tabs

The remaining tabs apply to the property you currently have selected:

• Transaction Filtering — exclude specific transactions from being sent.
• Transaction Identifier — choose how transactions are identified to avoid duplicates.
• Product Filtering — exclude specific products from event data.
• Product Identifier — choose which product ID (for example, variant ID or SKU) is sent.

Because these settings are per property, always confirm you're editing the right property before changing them.

The "multiple GA4 properties" warning

When you track more than one GA4 property on the same domain, TagFly shows a yellow warning banner:

Why it appears. Every property that is turned on receives the same set of events. If two properties track the same domain without a clear purpose, your data can become:

• Duplicated — the same Purchase or Page View is counted in both properties. If you later combine or compare them, revenue and conversions look inflated.
• Split — if you deliberately send different events to each property, no single property has the full picture, which makes reports incomplete.

This is not an error. The banner is a reminder to be intentional. Tracking multiple properties is fully supported and useful — as long as you know what each property is for.

What to do:

• Confirm each property is genuinely meant to receive these events. If a property is only for testing, send it fewer events or turn it off when you're done.
• During a migration, expect overlapping numbers while both properties run, and remove the old property as soon as the new one is verified.
• Don't treat two properties as independent sources and add their numbers together — they receive the same events, so the totals overlap.
• Give each property a clear name in GA4 (for example, "Prod", "Agency", "Test") so your team doesn't confuse them in reports.

Common use cases

• Migrating to a new GA4 property — run the old and new properties together to compare data, then remove the old one once the new property is verified.
• Sharing data with an agency — send conversions to both your own property and the agency's, so each side has direct access without cross-sharing permissions.
• Separating production and staging — use one property to test event configuration without affecting your main reporting property.
• A clean reporting property plus an experiment property — keep one property for official reports and another for testing audiences or advanced configurations.

Best practices

• The Measurement ID is the real destination. Two configurations pointing to the same Measurement ID are the same property and will always duplicate. Always confirm each property uses a different Measurement ID.
• Verify after adding a property. Use GA4 DebugView or the Realtime report to confirm the new property is receiving the events you expect. You can also cross-check with Pixel Health (Coverage Detail) to confirm events are firing end to end.
• Your existing setup is safe. Adding a property is additive — your current property keeps working, with no reconnect required and no interruption to tracking.

Need help?

If you run into any issues or want help configuring multiple GA4 properties for your store, reach out to the TagFly support team via the in-app chat — we're happy to walk through it with you.

Updated on: 29/06/2026