Google Ads API enforces daily minimum budget for Demand Gen campaigns

Google will begin enforcing a minimum daily budget for Demand Gen campaigns starting April 1, 2026.

What’s happening: The Google Ads API will require a minimum daily budget of $5 USD (or local equivalent) for all Demand Gen campaigns. The change is designed to help campaigns move through the “cold start” phase with enough spend for Google’s models to learn and optimize effectively. The update will roll out as an unversioned API change, applying across all buying paths.

Technical details:

• In API v21 and above, campaigns set below the threshold will trigger a BUDGET_BELOW_DAILY_MINIMUM error, with additional details available in the error metadata.
• In API v20, advertisers will receive a generic UNKNOWN error, with the specific validation failure referenced in the unpublished error code field.

The rule applies when modifying budgets, start dates, or end dates in ways that push daily spend below the $5 floor — covering both daily and flighted budgets.

Impact on existing campaigns. Current Demand Gen campaigns running below the minimum will continue serving. However, any future edits to budgets or scheduling will require compliance with the new floor.

Why we care. For advertisers and developers, this adds a new compliance layer to campaign management workflows. Systems will need updating to catch and handle the new validation errors before deployment.

The bottom line. Google is standardizing a minimum investment threshold for Demand Gen — prioritizing performance stability, while requiring advertisers to adjust budgets and automation accordingly.

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