Here's a clear and up-to-date breakdown of CBO vs ABO in Facebook Ads for 2025, including what's changed and what you should use for best results:

🚀 Facebook Ads: CBO vs ABO in 2025 (Explained!)
🧠 First, What Do These Terms Mean?
CBO = Campaign Budget Optimization
Facebook (Meta) controls how the budget is distributed across ad sets.

ABO = Ad Set Budget Optimization
You (the advertiser) control the budget at the ad set level.

🔄 CBO vs ABO: 2025 Update
As of 2025:

CBO is no longer mandatory, but it's recommended for scaling.

ABO is still available and widely used for testing or granular control.

Meta's AI and machine learning improvements in 2024–2025 have made CBO significantly smarter at budget allocation than in previous years.

📊 Main Differences:
Feature   CBO (Campaign Level)   ABO (Ad Set Level)
Budget Control   Meta distributes the budget   You manually set budget per ad set
Optimization Focus   Efficiency & scaling   Testing & precision
Best Use Case   Scaling proven audiences   A/B testing creatives or audiences
Ease of Management   Less hands-on   More manual control
Risk   Poor-performing ad sets may still get spend   You control every dollar

✅ When to Use CBO (2025 Best Practices)
Use CBO when:

You're scaling a campaign with proven audiences.

You want Meta's AI to automatically favor the best-performing ad sets.

You have 3–5 solid ad sets with some overlap in audience intent.

Pro Tips:

Set a minimum spend limit per ad set if you want to protect testing.

Use automated rules to cut underperforming assets quickly.

✅ When to Use ABO
Use ABO when:

You're testing new audiences or creatives.

You want tight control over how much each ad set gets.

You want to ensure each ad set spends enough to gather reliable data.

Pro Tips:

ABO is ideal for split tests, especially when budget fairness is critical.

Use this in early phases of a campaign lifecycle.

🧪 Advanced Hybrid Strategy
A lot of 2025 media buyers now use:

ABO for testing

CBO for scaling the winners

Example Flow:

Week 1: Run ABO to test 4 audiences at $20/day each.

Week 2: Move top 2 performers into a new CBO campaign at $100/day.

Week 3+: Let Meta optimize spend to scale best performer.

🔚 Conclusion
In 2025, CBO is smarter and more efficient, especially for scaling. But ABO remains essential for controlled testing and budget separation. Smart advertisers use both strategically—test with ABO, scale with CBO.