Change History

Change History is a detailed audit log in Google Ads that tracks every modification made to campaigns, ad groups, keywords, bids, budgets, and settings. It records what changed, who made the change, and when it occurred, providing full accountability across manual edits, automated rules, and API actions.

Key Takeaways

• Records all account modifications with timestamps and user attribution
• Tracks changes from manual edits, automated rules, scripts, API calls, and Google auto-apply
• Essential for diagnosing sudden performance shifts by correlating changes with metric movements
• Filterable by date range, change type, user, and campaign
• Retains data for up to two years in the Google Ads interface

What Is Change History

Change History is the built-in audit trail for every Google Ads account. Accessible under Tools > Troubleshooting > Change history in the 2026 interface, it logs modifications across all account elements. Each entry includes:

Field	Description
Date and time	Exact timestamp of the change
Who	User email, “Automated rule,” “Google Ads system,” or API client
What changed	Entity type (campaign, keyword, bid, ad, etc.)
Change type	Created, modified, removed, enabled, paused
Old value	Previous setting before the change
New value	Updated setting after the change
Campaign/Ad group	Where the change occurred

How It Works

Google Ads automatically logs every modification without requiring any setup. Changes appear in the log within minutes of being made. You can filter the history by:

1. Date range — Narrow to the exact period when performance shifted
2. Change category — Bids, budgets, status, targeting, ads, extensions, or settings
3. Changed by — Specific users, automated systems, or auto-apply recommendations
4. Campaign or ad group — Isolate changes to specific parts of the account

The log distinguishes between changes made by human users (shown by email), automated rules (labeled “Automated rule”), Google Ads Scripts, API integrations (shown by developer token name), and Google system changes from auto-apply features.

Practical Example

A campaign’s CPA jumps from $25 to $45 overnight. Using Change History:

• Filter to the campaign, date range: yesterday
• Discovery: An automated rule increased bids by 30% on 150 keywords at 2:00 AM
• The rule condition was too broad (CTR > 1% instead of CTR > 3%)
• Additionally, Google auto-applied a recommendation to add broad match keywords at 4:00 AM
• Both changes compounded, driving up costs

Resolution: Revert the bid changes, fix the rule condition, disable auto-apply for keyword match type changes, and monitor for 48 hours.

Why It Matters

Change History is the primary diagnostic tool for performance investigations. When metrics shift unexpectedly, the change log is the first place to look — before blaming market conditions or competitors. It is equally important for agency accountability, ensuring that team members and automated systems are making changes consistent with the account strategy. For accounts using the Google Ads API, Change History provides an external verification layer to confirm that programmatic changes were applied correctly.