Choose another country or region to see content specific to your location.

GA4 Post-Migration Checklist: 21 Actions for a Clean Break from UA

Picture of Mostafa Daoud

Mostafa Daoud

Table of Contents

You Can Listen to The Blog from Here

Quick Orientation

UA is gone, GA4’s event model is here, and the margin for error is razor-thin. This living guide walks you through seven disciplined steps—starting with a bullet-proof implementation audit—so you can trust every dashboard that follows and unlock GA4-only features such as predictive audiences, BigQuery exports, and cross-platform identity stitching. Miss Step 1 and every subsequent insight will wobble.


1 Verify Your GA4 Implementation

1.1 Confirm Real-Time Data Flow

Open Realtime; fire a test page-view or event from desktop and mobile. If the hit doesn’t show within 30 seconds, jump to DebugView and switch on debug_mode to trace the payload in forensic detail.

Pro Tip: Keep a second tab on your production property while testing your dev container—DebugView labels events with a green “DebugDevice” badge so you don’t pollute live data.

1.2 Audit Key Events & Parameters

Compare the live Events list against your migration tagging matrix. For e-commerce, verify that every purchase hit carries the non-negotiables: transaction_id, value, currency, and an array of items each with item_id and quantity.
If any required field is blank, GA4 will still log the event—but downstream revenue reports and predictive models will break silently.

1.3 Spot-Check Data Consistency

Pivot the Events report by device, traffic channel, and geography. Large gaps often flag duplicate tags (double-counting on web but not app) or consent-mode misfires on specific regions. Cross-reference UA vs. GA4 counts during the same hour; expect up to ±10 % variance due to the new session logic, not 50 %.

2. Rebuild Your Reporting & Analysis Workflows

Universal Analytics views are extinct; your shiny GA4 property is the new command center. 

Here’s how to resurrect every must-have dashboard, keep analysts sane, and actually exploit GA4’s event-first brain rather than spending the next quarter muttering “Where did that report go?”

2.1 Map Your Old UA Views to GA4 Explorations & Looker Studio

  1. Start with Funnel Exploration. GA4’s Funnel Exploration replicates—and frankly surpasses—UA’s Goal Funnels by letting you toggle open vs. closed steps, retro-fit conditions, and segment on the fly.
  2. Port top UA dashboards into Looker Studio. Grab a free GA4 Looker template, swap the data source, and you’re 80 % home before coffee is cold.
  3. Save custom Explorations to the Library. Anything you build in Explorations can be surfaced for non-power users via the report Library—think of it as your old “Saved Reports” folder reincarnated.

Quick sanity check: If the KPI never existed as an event, create the tag first, then the report. GA4 shows zero love for retroactive page-view goals.

2.2 Embrace GA4’s New Metrics & Dimensions

UA’s Sessions, Users, Pageviews trio is now augmented (some say upended) by Engaged Sessions, Event Count, and User Lifetime metrics .

Teach marketers why “Engagement Rate” replaces “Bounce Rate,” and warn execs that cross-property session_start events may inflate counts compared with legacy data.

2.3 Automate Distribution & Drill-Down with BigQuery

  1. Turn on the free BigQuery export. Even standard (non-360) properties ship up to 1 M events/day to BigQuery at zero cost—plenty for most brands (Google Help).
  2. Use the event schema as your master dataset. The export delivers every parameter at row-level granularity, ready for SQL and BI joins.
  3. Stitch UA history for trend lines. Tools like Funnel or a short UNION query let you stack UA’s ga_sessions_YYYYMMDD tables beneath GA4 events so YoY charts survive the apocalypse.

2.4 Customize Detail Reports for Stakeholders

In GA4 you can add/remove metrics, swap charts, and pin filters directly inside any Detail Report—no more hard-coded columns. Build role-based views (e.g., Paid Media vs. Product) once and publish to the Library so each team lands on the numbers that matter, minus the tab-hunting.

2.5 House-Rules for a Living Reporting Stack

GuardrailRationaleReview Cadence
No channel with CAC > 40 % of 12-mo LTV gets scale.Ties GA4 ROAS dashboards to profit, not vanity.Monthly budget retro
All new events must carry source & campaign params.Saves you from “(not set)” nightmares in Explorations.At tag deployment
Exploration templates get version numbers.Prevents silent metric definition drift.Quarterly

These rules aren’t fancy—they’re survival gear. Bolt them onto your BI layer and the reporting machine purrs instead of squeaks.

Google Analytics 4 rewards teams that keep the configuration lean, descriptive, and forward-compatible. 

The focus in this section is threefold: 

(1) trim noisy auto-events so dashboards stay readable; (2) give every business-critical hit a concise, quota-friendly taxonomy before the first visit rolls in; (3) wire up audiences, predictive metrics, and raw-data exports so marketing and data-science crews can act, not guess. 

Miss any one of these and GA4’s shiny interface quickly turns into a thicket of “(not set)” rows, 40-character truncations, and half-populated remarketing lists.

3 Optimize Your GA4 Configuration

3.1 Fine-Tune Enhanced Measurement

Enhanced Measurement fires six out-of-the-box events—scroll, file_download, site_search, video_start, outbound_click, and page_view—every time a page loads.


Left fully enabled, scroll hits alone can double daily event volume and drown signal in noise; disable any metric your analysts don’t report on, or switch to a Tag Manager rule that pushes scroll at 50 % only.


If you run multiple domains on one tag, also configure cross-domain measurement in Tag Settings → Configure your domains so GA4 stitches sessions instead of spawning new users every click.

3.2 Refine Event Parameters & User Properties

GA4 caps event-parameter names at 40 characters and values at 100; longer labels truncate silently and break Looker joins.


Custom dimensions share a hard limit—50 event-scoped slots on a standard property—so register only what downstream reporting truly needs before burning quota.

Follow Google’s naming rules: lower-case, underscore-spaced, start with a letter, and avoid reserved prefixes to keep implementation scripts error-free.

Document those rules in a sheet and mirror them in GTM tag names (e.g., GA4 event – cta_click) for future auditors.


Create user-scoped properties early; GA4 can’t backfill historical values after first collection, and archived properties are gone for good.

3.3 Build High-Intent Audiences for Remarketing & Analysis

Audiences live inside GA4—Google Ads can consume them but not edit them—so define segments where the data sits.
Blend behavioural rules (add_to_cart, view_item) with predictive metrics such as purchase_probability for razor-sharp remarketing lists once the model sees ≥1 000 purchasers and churners in 28 days.

3.4 Unlock Predictive Metrics & BigQuery Export

Predictive metrics appear only when the purchase or in_app_purchase events fire with complete parameters and the property sustains model quality.
Turn on the free BigQuery export—standard properties now ship up to one million raw events per day at no cost—to bypass GA4’s 14-month retention ceiling and power SQL-level analysis.
If you still need year-over-year views inside BI tools, stack UA history beneath GA4 tables with the Data API or a Looker Studio merge .

3.5 Set Data Retention & Governance Guardrails

GA4 defaults to two-month user-level retention; extend to 14 months in Admin → Data Settings → Data Retention before analysts discover winter’s cohort has vanished (GA4.com).
Publish house rules—“no new event ships without source and campaign”, “CAC must stay under 40 % of 12-mo LTV”, “Exploration templates get version numbers”—to keep the configuration from drifting as teams scale.
Standard reports store aggregate data past 14 months, but Explorations do not; when long-term breakdowns matter, query BigQuery or stick to aggregate report tables.

GA4’s headliners—predictive analytics, cross-platform identity stitching, and raw-event BigQuery pipelines—turn a basic migration into an upgrade. Nail the eligibility thresholds, switch on User-ID everywhere users log in, and pipe the firehose into BigQuery before reports start sampling. Do that trio right and you unlock machine-learning audiences, device-spanning funnels, and SQL-grade flexibility that UA never offered.

4 Leverage GA4-Only Features

4.1 Predictive Metrics & Insights

Why it matters. GA4 trains models on your first-party event stream and surfaces three forward-looking KPIs—purchase probability, churn probability, and predicted revenue—along with ready-made audiences like “Likely 7-day purchasers.”

  • Hit the eligibility bar. A property needs at least 1 000 purchasers + 1 000 churners in the last 28 days before the model even runs, so crank up conversion tagging first.
  • Spin up predictive audiences. In Audiences → New → Predictive, combine “purchase probability > 90th percentile” with recent add_to_cart for remarketing lists that waste zero ad spend.
  • Harvest automated insights. The Insights panel on GA4’s Home flags anomalies (traffic spikes, revenue dips) in real time; use Custom Insights to ping Slack or email when CAC pops past target.
  • Guardrail. Models refresh daily but only on fresh data—pause for two weeks and predictions flatline. Remind media teams before campaign blackouts.

Pro Tip: Treat predictive audiences as tiers in Google Ads, bidding hardest on the “Likely 7-day purchasers” list while still nurturing “Likely churners” with softer CTA creative.

4.2 Cross-Platform Tracking with User-ID

Why it matters. Users bounce between iOS, Android, and web; GA4’s event model plus User-ID lets you follow them without stitching in BI after the fact. 

  1. Emit user_id on every logged-in hit (web tag, Firebase SDK, server-side GTM). GA4 merges device IDs under one profile, unlocking Device overlap and Path exploration views.
  2. Re-tag your app with the same Measurement ID. Mixing iOS app_id, Android app_id, and web stream into one property fuels true cross-device funnels.
  3. Benchmark deltas. Expect sessions to dip a few percent (de-duped devices) while users and LTV jump. Set stakeholder expectations early.

Quick sanity check: If you still see separate “(app)” and “(web)” audiences in reports, the streams aren’t stitched—double-check IDs.

4.3 BigQuery Export for Advanced Analysis

Why it matters. GA4’s UI caps retention at 14 months and samples ad-hoc queries. BigQuery stores raw events forever and answers SQL in seconds.

  • Turn it on—free. Standard properties now export up to 1 M events/day at no cost; storage in the BigQuery sandbox runs ~$0 for many midsize sites.
  • Daily vs. streaming. Batch exports drop once per day; flip Streaming only if you need hour-level freshness and budget for tiny per-MB charges.
  • Master the schema. GA4 writes events_YYYYMMDD tables with nested event_params and items; same shape for web and app, perfect for UNIONs.
  • Blend UA history. Stack UA’s ga_sessions_* tables beneath GA4 to preserve YoY charts and feed attribution models.

Guardrail: If you flirt with the 1 M-event cap, exclude noisy events (scroll, video_start) or upgrade to 360 before exports pause

4.4 Tie It All Together

  1. Feed predictive audiences into Google Ads for smart bidding.
  2. Join GA4 + CRM IDs in BigQuery to model true LTV and offline conversions.
  3. Schedule automated insights to Slack, turning anomalies into sprint tickets within hours not weeks.

When these three features—predictive metrics, User-ID stitching, and BigQuery exports—fire in concert, GA4 stops feeling like a forced upgrade and starts acting like the analytics platform UA always wanted to be.

5 Troubleshoot Common GA4 Issues

Even a flawless migration will surface oddities the first time someone lines up GA4 against five years of UA dashboards. This section arms you with a rapid-diagnosis playbook so you can explain 10 % variances with a straight face, recover “missing” conversions, and tame GA4’s thresholding warnings before they spin into a Slack fire-drill.

5.1 UA vs. GA4 Discrepancies—Know the Usual Suspects

MismatchPrimary CausesFast Check
Sessions ±5–15 %GA4 estimates sessions, doesn’t restart at midnight, treats campaign-parameter changes as a single sessionCompare same-day session counts; time-zone shift alone can move UA numbers by 3–4 %
Conversions off by 1× per sessionUA goals fire once per session; GA4 lets you count every event occurrenceToggle “Count” to Once per session in Conversions settings to mimic UA 
Revenue gapstransaction_id missing or inconsistent; item arrays malformedValidate transaction_id, currency, value in DebugView before blaming GA4 math

Quick sanity check: If gaps exceed 20 %, look first for duplicate tags or consent-mode traffic drops before rebuilding SQL.

5.2 Missing or Sampled Data—Spot Thresholding & Retention Gotchas

  • Thresholding banner. A red triangle plus “thresholding applied” means GA4 withheld rows to protect user privacy—often triggered by demographic dimensions or small predictive audiences. Swap to a non-sensitive dimension or query BigQuery raw events.
  • 14-month cliff. Explorations respect the property’s retention window (default 2 months). Extend to 14 months in Admin → Data settings and push anything longer to BigQuery.
  • Behavioral modeling gaps. If you rely on Consent Mode, GA4 needs “Advanced” implementation on every page to back-fill modeled data; partial rollouts create Swiss-cheese funnels.

5.3 Events Fire but Conversions Don’t—Classic Misconfigurations

  1. Event not marked as a conversion. Flip the toggle in Admin → Events and wait up to 24 h for reports.
  2. Broken tag or parameter mismatch. Open DebugView, look for the event; if missing required parameters (value, currency), GA4 logs the hit but omits it from revenue.
  3. Measurement Protocol hiccups. Double-check api_secret and stream ID when sending server-side events.

Pro Tip: Create a dummy purchase on staging every morning; if the Slack alert doesn’t fire, you’ll know before Finance does.

5.4 Real-Time & Attribution Quirks—Know the Limits

  • Real-time tile blind spots. GA4 filters spam/bot traffic aggressively; “missing” users often land there .
  • Session fragmentation. Cross-domain clicks without linker parameters or missing User-ID can split one user into multiple sessions, skewing attribution.

5.5 When to Escalate

SymptomEscalate ToBecause
Threshold banner persists after dimension swapData EngineerOnly BigQuery raw can bypass aggressive privacy filters.
Revenue zero for an entire dayDev / Tag OpsLikely container publish failure or consent-mode default block.
Predictive metrics vanishedAnalystProperty fell below 1 000 purch. / churners in 28 days; need fresh conversion volume.

Stomp out these fires fast and the rest of your migration journey feels like routine maintenance instead of crisis management.

6 Educate & Empower Your Team on GA4 Changes

A shiny GA4 property is only as good as the people interpreting its numbers. Treat enablement like any other product launch: roll out role-specific onboarding, stand-up a Center of Excellence, and bake a release-notes cadence into sprint rituals so dashboards and decisions evolve together.

6.1 Deliver Role-Based Training Playlists

PersonaMust-Know TopicsFast-Track Resources
Marketing managersEngaged sessions, attribution settings, audience building3-hour “Google Analytics 4 for Marketers” path on Skillshop/Analytics Academy
Data analystsExplorations, BigQuery export, GA4 SQL schemaGA4 developer catalog + code samples on Google Developers
Stakeholders / execsNew KPIs (Engagement Rate > Bounce Rate), predictive metrics, privacy limits60-min internal live demo + one-page KPI glossary

Pro tip: Pair every e-learning module with a property sandbox so learners tag, query, and break things safely before they touch prod.

6.2 Stand-Up a GA4 Center of Excellence (CoE)

A CoE gives busy teams a single source of truth for naming rules, governance, and troubleshooting. Anchor it on five pillars—Standardization, Asset reuse, Coaching, Continuous improvement, Metrics stewardship—borrowed from mature CoE playbooks.

Launch checklist

  1. Charter & KPIs. Define success as “<3 % data-quality tickets per quarter” and “<7 days to adopt new GA4 features.”
  2. Coach network. Nominate one “analytics champion” per squad; rotate them through quarterly GA4 deep-dives.
  3. Asset hub. Store tagging matrices, Exploration templates, and Looker dashboards in a shared drive—versioned, permissioned, and searchable.
  4. Slack war-room. #ga4-help channel with a 2-hour SLA for tier-1 questions keeps email-free fire drills at bay.

6.3 Embed GA4 in Daily Rituals

  • Sprint demo: Show a live DebugView or Exploration at each sprint review—analytics visibility rises, tagging gaps surface early.
  • Release retro: Add “GA4 impact” as a line item in post-release retros; report win/loss against targets within 48 h.
  • Morning heartbeat: A scheduled Looker Studio email hitting inboxes by 9 a.m. keeps KPIs front-of-mind without another login.

6.4 Stay Ahead of Product Updates

GA4 still ships new fields, UI tweaks, and privacy safeguards almost monthly. Make release tracking a recurring task:

  1. Subscribe to the official Google Analytics changelog RSS or mailing list.
  2. Summarize impact in a two-bullet Slack post: “New user_location param → no action.” / “Attribution refresh: update Looker formulas by Friday.”
  3. Triage in the CoE backlog; size effort and assign owners during backlog grooming.

6.5 Measure Enablement ROI

  • Uptake metric: % of marketers actively building or editing Explorations—target 60 %+ within three months.
  • Support metric: Mean time-to-resolution for GA4 tickets; drive below 48 h.
  • Impact metric: GA4-driven optimisations shipped per quarter (e.g., audience refresh, funnel fix, budget shift).

When training turns into measurable adoption and a living governance loop, GA4 evolves from “new tool” to shared lingua franca—no more analyst bottlenecks, no more dashboard déjà vu.

7 Plan for a Long-Term Analytics Strategy

The hard part—migration, validation, and quick-win reporting—is behind you. Now the mission is to turn GA4 into a durable decision-engine that outlives new privacy laws, changing ad stacks, and yet-to-be-invented channels. Three pillars keep the strategy upright: event-aligned KPIs, deep integrations, and a living upgrade cadence.

7.1 Align KPIs to GA4’s Event-Based DNA

Universal Analytics let you bolt goals onto a session; GA4 wants you to define Key Events that are the business outcomes. Start by translating every board-level metric into one or more clearly named events:

Business QuestionGA4 Key Event(s)Why It Works in 2025
Net-new pipelinequalified_lead_submitSurfaces in Ads attribution & BigQuery joins
Subscription retentionplan_renewal, subscription_cancelFuels churn-probability models
Product adoptionfeature_use (param =feature_name)Drives path analysis & in-app messaging

  • Guardrail → Keep names under 40 chars and values under 100 or they’ll truncate silently.
  • Mark revenue-bearing or north-star events as Key Events (GA4’s new conversion flag) so they flow into attribution and predictive models.
  • Re-score KPIs each quarter: if a metric can’t tie back to a Key Event, either tag it or kill it—no zombie dashboards.

7.2 Integrate GA4 With the Wider Marketing & Data Stack

IntegrationPrimary WinSetup Tips
Google Ads & DV360Auto-sync GA4 audiences & conversion values for Smart BiddingLink properties, import Key Events, layer predictive audiences
BigQueryUnsampled, forever retention + SQL joinsFree up to 1 M events/day; use scheduled queries to blend UA history
CRM / CDPClosed-loop ROI & LTV modelsExport GA4 user_ids + GCLIDs; re-import offline revenue
Consent-Mode & server-side GTMData continuity under privacy lawsRoute hits through your domain; enables advanced modelling

Cross-stack joins future-proof analytics when cookie windows shrink or ad platforms wall off data. GA4’s 2025 updates even add direct Annotations on shared reports—perfect for tagging campaign launches or site outages so marketing, data science, and execs see the same context.

7.3 Run a “Release-Notes” Cadence

GA4 shipped more than a dozen net-new features in the first half of 2025—AI-assisted trend detection, generated audience suggestions, and percentage columns in every detail report.


Treat the platform like a SaaS product you own, not a black-box vendor tool:

  1. Subscribe to the “What’s New in GA” feed.
  2. Triage monthly: For each change, label No-action / Internal update / Stakeholder update.
  3. Annotate major releases directly on reports so future analysts know why numbers jumped.
  4. Quarterly refactor: Fold new features (e.g., predictive churn precision bump) into audience logic or KPI targets.

7.4 Bake Privacy & Resilience Into the Roadmap

  • Switch to server-side tagging to cut ad-blocker loss and control PII handling.
  • Adopt Consent Mode v2 across every page; GA4’s behavioural modelling fills unavoidable gaps.
  • Keep data retention maxed at 14 months in the UI, forever in BigQuery.

Regulators tighten rules yearly; a first-party, event-centric architecture plus flexible export keeps analysis legal and intact.

7.5 Operationalise Continuous Optimisation

  1. Monthly heartbeat: Review CAC:LTV ratios by acquisition channel straight from BigQuery; pause spend that drifts >40 % of 12-mo LTV.
  2. Experiment loop: Push at least one new Key Event–driven A/B test per sprint—small, compounding wins still beat “swing-for-the-fences” projects.
  3. Scorecard: Track GA4-driven actions shipped as an OKR; if insights don’t spawn changes, the platform is ornamental.

Final Thought

A migration without a long-term operating model is just technical debt on a timer. Anchor KPIs to events, wire GA4 into every revenue and engagement system, and treat release notes like security patches. Do that, and your analytics practice stays two steps ahead of product pivots, privacy shake-ups, and whatever acronym Google rolls out next.

Picture of Mostafa Daoud

Mostafa Daoud

Mostafa Daoud is the Interim Head of Content at e-CENS.

Related resources