CBO vs ABO: Which one should you use?

CBO - Campaign Budget Optimization 

Meta controls which ad sets get the spend of the budget. 

Works well when you have ad sets that are loaded with successful creatives and just want Meta to algorithm to cycle through them.  

ABO - Ad Set Budget Optimization 

You manually control the budget per ad set. Use this Good when you're testing new stuff because you can control exactly how much each creative spends.

Testing phase = ABO. You want control. You want equal spending on each creative so you can compare fairly.

Scaling phase = CBO. You've found winners. Let the algorithm put money where it performs best.

I was doing it backwards. Always complained why one ad set or one creative gets all the budget, and the rest never get a fair chance.

How I test creatives without killing my winning campaign:

I never test inside my winning campaign. Ever.

Here's my exact structure:

Campaign 1 WINNERS (CBO)

• 1 ad set

• All proven creatives

• This is your money maker. Don't touch it.

Campaign 2 TESTING (ABO)

• Separate the campaign completely

• $50-100/day budget

• Equal budget per ad set

• Run for 3-5 days minimum

• If a creative wins here, move it to Campaign 1

Simple. Clean. No interference.

How to know if a creative is a winner:

Don't judge too early. Give it at least 3 days and a $50 minimum spend before making any decisions.

A winner for me means: CPA is at or below target AND it's getting consistent results, not just one good day.

The mistake most people make:

They test inside their winning campaign. New creative steals budget. Winning creative stops getting spent. Everything breaks. They panic and kill the whole thing.

Keep testing completely separate. Always.

Quick summary:

ABO for testing. 

CBO for scaling. 

Never mix the two. 

Never test inside a winning campaign.