The GA4 Setup Checklist

Go to Admin > Property Settings and verify you have not accidentally created duplicate properties. Duplicate properties split your data and make comparisons unreliable. If duplicates exist, decide on one canonical property and remove the tag from all pages on the others.

Admin > Property Settings > Time Zone. Choose the time zone where your business operates, not the default. Mismatched time zones make daily and weekly reports misleading because sessions can appear on the wrong date.

Admin > Property Settings > Currency. Set this to the currency your transactions are processed in. GA4 does not convert retrospectively, so wrong currency affects all e-commerce and revenue reporting permanently.

Admin > Data Settings > Data Retention. The default is 2 months. Switch it to 14 months. This extends how far back you can run custom explorations and funnel reports. Standard reports are unaffected, but explorations cut off at the retention window.

Admin > Data Settings > Data Collection > Google Signals. Toggle this on and click through the acknowledgement. This enables cross-device reporting and improves demographic data. Without it, a user on mobile and then desktop looks like two users.

Admin > Data Streams. You should see one stream for your website. If you see multiple streams for the same domain, you are likely double-counting sessions. Audit your tag implementation to confirm only one Measurement ID is firing.

Admin > DebugView. Open your website in a separate tab with the GA4 DebugView Chrome extension active, then browse around. You should see events appearing in real time. If nothing shows, your tag is not firing. If you see duplicate events, your tag is firing twice.

If you use Google Tag Manager, check your website source code to confirm the GA4 gtag is not also hardcoded in the HTML. Having both fires every event twice and doubles all your session counts. Search your theme files or page source for your Measurement ID (G-XXXXXXXXXX).

Admin > Data Streams > your stream > Enhanced Measurement. Review the list. Scroll tracking, outbound clicks, site search, and video engagement are usually worth keeping on. File downloads is worth keeping on. Disable any event type your site does not support, as phantom events add noise.

Admin > Data Streams > your stream > Configure Tag Settings > Define Internal Traffic. Add your office IP address with the traffic_type value set to 'internal'. To find your IP, search 'what is my IP' in Google. If your team works from multiple fixed locations, add each one.

Admin > Data Settings > Data Filters. Create a filter of type 'Internal Traffic', set it to exclude, and activate it. Note: new filters only apply to data from the moment they are activated. They do not clean historical data.

If developers work on the site remotely, ask them for their IPs and add those to the internal traffic definition. If you have a staging domain, add a separate hostname filter to exclude traffic from that subdomain entirely.

New data filters default to 'Testing' state, which means they are flagged but not excluded. Go back to Admin > Data Filters and confirm your internal traffic filter shows 'Active'. In Testing mode, your own visits are still counted in reports.

Admin > Conversions. Review every event marked as a conversion. Remove session_start, page_view, and any auto-marked event that is not a genuine business action. Inflated conversion counts make your cost per conversion look artificially low.

Admin > Conversions > New Conversion Event. If you have a custom event firing when a form is submitted (e.g. form_submit, lead_form_complete), enter that event name here and save. If you do not have that event yet, set it up first via Google Tag Manager using a Form Submission trigger.

If you use a pop-up or embedded sign-up form and have an event firing on successful subscription, mark it as a conversion. If the thank-you step loads a separate URL (e.g. /thank-you-for-subscribing), create a Page View event for that URL in GTM and mark it as a conversion.

If you use Calendly, TidyCal, or a similar tool, the confirmation page typically loads in an iframe and GA4 will not see it automatically. Create a cross-domain tracking event in GTM that fires when the booking confirmation is reached, or use the Calendly GTM integration to push a custom event.

If a PDF, checklist, or lead magnet download is a business goal, create a File Download conversion. Enhanced measurement tracks file_download automatically, so go to Admin > Conversions, find file_download in your event list, and toggle it as a conversion. Optionally add a Link URL parameter filter to limit it to your specific file URLs.

Enhanced measurement includes scroll tracking but only fires at 90% scroll depth. If you have long-form posts or sales pages, create additional events at 25%, 50%, and 75% in Google Tag Manager using a Scroll Depth trigger. This tells you where people are dropping off, not just who finishes.

Enhanced measurement tracks all outbound clicks, but the data is noisy. In GTM, create a specific event (e.g. click_booking_link) that fires only when someone clicks your Calendly or booking link. This gives you a clean count of intent without filtering through all outbound clicks.

Enhanced measurement tracks YouTube embeds automatically. For Vimeo or native HTML5 video, create a custom event in GTM using an Element Visibility or YouTube / Vimeo API listener. At minimum track: video_start and video_complete. These tell you whether your video content is doing anything.

Create a page_view event filtered to your /contact URL and mark it as a conversion, or at minimum a key event to monitor in explorations. A high volume of contact page visits that do not convert to form submissions signals a friction problem on the page.

Admin > Attribution Settings > Reporting Attribution Model. GA4 defaults to Data-Driven Attribution, which is fine if you have enough conversion data (at least a few hundred conversions per month). If you are earlier stage, switch to Last Click so attribution logic is predictable and you can read it without a statistics degree.

Admin > Attribution Settings. Acquisition lookback window defaults to 30 days, engagement to 3 days. If your sales cycle is longer (common for B2B or high-ticket offers), extend the acquisition window to 60 or 90 days. Otherwise, campaigns that contribute to a conversion months earlier get no credit.

Admin > Audiences > New Audience. Build an audience of users who visited your services page, pricing page, or booking page but did not complete a conversion. This audience can be pushed to Google Ads for retargeting, and it also tells you in Audience reports how many high-intent visitors you are losing per month.

Build a second audience of users who completed your key conversion event. Use this in explorations to see what content, channels, and pages converted users visited before converting. This is where you find which traffic source generates leads, not just sessions.

Reports > Library > Create New Report > Detail Report. Add dimensions: Landing Page. Add metrics: Sessions, Conversions, Session Conversion Rate, Engaged Sessions. Save and add to your navigation. This tells you which pages are driving business, not just which pages get clicks.

Explore > Funnel Exploration. Map out the pages or events in your main conversion path (e.g. Blog Post > Services Page > Contact Page > Form Submission). GA4 shows you drop-off at each step. If more than 70% of people are dropping between two specific steps, that is the fix to prioritise.

Explore > Free Form. Add dimension: Session Default Channel Group. Add metrics: Conversions, Session Conversion Rate, Engaged Sessions, Average Engagement Time. This gives you a real read on which channels are doing work, not just which ones are sending the most traffic.

GA4 does not natively support annotations, but you can log them in a shared Google Sheet with date, change type, and description. Add an annotation every time you run a campaign, publish a major piece of content, make a site change, or adjust your tag setup. Without annotations, a traffic spike six months from now is unexplainable.