GA4 Data Retention: What Happens to Your Data After 14 Months

GA4 has a data retention limit that most people don’t know about until they try to pull a year-over-year comparison and discover half the data is gone.

By default, GA4 keeps user-level and event-level data for only 14 months. After that, it’s deleted and unrecoverable from GA4’s interface.

What Gets Deleted

Affected (User/Event-Level Data)

These disappear after the retention period:

• Explorations (Free Form, Funnel, Path, etc.) — can’t query data older than retention window
• User-scoped data — individual user journeys, user properties
• Event-scoped data — individual event parameters, custom dimensions
• Audience membership — users who haven’t returned fall off audience lists

NOT Affected (Aggregated Reports)

These are preserved indefinitely:

• Standard reports (Traffic, Engagement, Monetization, etc.)
• Aggregated metrics (total users, sessions, pageviews, revenue)
• Conversion counts (total conversions per event)
• Real-time data (always current 30 minutes)

Translation: You can see “we had 10,000 sessions last January” in standard reports forever. But you can’t build an Exploration breaking those sessions down by user segments, custom dimensions, or individual paths after 14 months.

Changing the Retention Period

GA4 → Admin → Data Settings → Data Retention

Two options:

• 2 months (default for some properties)
• 14 months (maximum)

Set it to 14 months immediately. There’s no reason to use 2 months unless you have a specific compliance requirement to minimize data storage.

This change is NOT retroactive — it only affects data going forward. If your property has been on 2-month retention, data older than 2 months is already gone.

The BigQuery Solution

For data older than 14 months, export to BigQuery. GA4 has a free daily export:

Setup

1. GA4 → Admin → BigQuery Links → Link

2. Select your GCP project (create one if needed)

3. Choose export type:

   • Daily (free, next-day data)
   • Streaming (paid, real-time, ~$0.05 per GB)

4. Data exports to analytics_PROPERTY_ID.events_YYYYMMDD tables

Cost

BigQuery charges for storage and queries:

• Storage: $0.02/GB/month (first 10GB free)
• Queries: $5/TB scanned (first 1TB/month free)

A typical ecommerce site with 100K events/day uses ~30GB/month in BigQuery. Cost: ~$0.60/month for storage.

If you’re spending $1K+/month on ads, BigQuery is basically free insurance for your historical data.

What You Can Do With BigQuery Data

• Year-over-year comparisons with full event detail
• Custom attribution modeling beyond GA4’s built-in models
• Connect to Looker Studio for dashboards that query raw data
• User-level cohort analysis (LTV, repeat purchase patterns)
• Cross-reference with ad platform data for true ROAS calculation

The GDPR Angle

GA4’s data retention is partly a privacy compliance feature. GDPR requires data minimization — you shouldn’t keep personal data longer than necessary.

14 months is generally defensible for legitimate interest in analytics. If you export to BigQuery, the same data minimization rules apply to your BigQuery tables. Set table expiration policies to match your legal requirements.

For consent-related tracking concerns, see our Consent Mode v2 implementation guide.

What to Do Right Now

1. Check your current retention setting: GA4 → Admin → Data Settings → Data Retention
2. Set it to 14 months if it isn’t already
3. Enable BigQuery export if you need historical data beyond 14 months
4. Set a calendar reminder for 12 months from now to verify your data pipeline is working

The worst time to discover your retention period is when you need the data for a board presentation or year-end review and it’s already been deleted.

Need help setting up your GA4 correctly? Run a free tracking scan — we check your configuration, event tracking, and conversion setup in 60 seconds.