The debate between ABO and CBO has existed for years, but in 2025 - under the Andromeda delivery system - things have changed dramatically.

Both still work.
Both have a purpose.
Both can scale profitably.

But they perform very differently now compared to the pre-iOS era.

This guide explains exactly when to use ABO vs CBO in 2025, and the new rules that determine which one will deliver more stable performance for your account.

The Old Rule (2018–2022):

• ABO = control
• CBO = automation

The New Rule (2024–2025 Andromeda Era):

ABO = precision testing.
CBO = scalable stability.

Both still matter - but the role of each has shifted.

Why This Changed

Andromeda altered how budgets behave:

• Faster exploration
• More aggressive pocket shifting
• Heavy creative dependence
• Stronger clustering behavior
• Higher volatility at low spend
• Improved campaign-level prediction

CBO became smarter, and ABO became more specialized.

When ABO Works Best in 2025

ABO shines in three situations:
testing, controlling, and isolating.

1. Creative Testing (ABO = best testing environment)

ABO lets you:

• allocate equal spend to each creative
• isolate signals
• avoid one creative stealing all the spend
• compare angles more fairly

Most advertisers use ABO for:

• early-stage creative tests
• concept tests
• hook tests
• angle validation

Rule:

ABO = Creative Testing
until you find a winner.

2. Testing New Audiences or Segments

When exploring a new:

• interest cluster
• demographic pocket
• market
• region
• lookalike range

ABO is ideal because you control the distribution.

Rule:

ABO = exploration where fairness matters.

3. Testing Sensitive Budget Scenarios

If you need guaranteed daily spend per ad set:

• small audiences
• seasonal segments
• localized targeting
• remarketing tiers

…ABO gives predictable pacing.

When CBO Works Best in 2025

CBO is the default for scaling.

Andromeda’s predictive model performs best when budgets flow freely.

1. Scaling Campaigns (CBO = best for stable scaling)

CBO excels when:

• you have validated creatives
• multiple audiences available
• system knows your buyer
• you want smooth, long-term results

CBO reduces:

• manual interventions
• audience cannibalization
• volatility
• pacing issues

Rule:

CBO = Scaling.

2. Audience Portfolios

CBO thrives when managing:

• Broad
• several interest clusters
• lookalikes
• historical winners
• warm audiences

CBO uses performance signals to route spend intelligently.

ABO cannot do this efficiently.

3. When Creative Fatigue Is Frequent

In CBO, when one creative fatigues, Meta can dynamically shift spend to another ad set.

In ABO, fatigue kills the entire ad set.

Rule:

If fatigue is a recurring issue, CBO protects ROAS better.

How Budgets Actually Flow in 2025 (Important)

Because Andromeda is predictive, budget flow is based heavily on:

• creative cluster performance
• expected conversion probability
• real-time user pocket performance
• stability of signals
• likelihood of future cost efficiency

This makes CBO significantly stronger for:

• smoothing volatility
• reacting to competition
• adjusting to pocket shifts

ABO can’t adapt at this level.

How to Use ABO and CBO Together (The 2025 Ideal Structure)

The best Meta advertisers run this setup:

1. Creative Testing Campaign - ABO

• 3–6 creatives at a time
• Broad or simple interest
• Equal budget distribution
• 72–96 hour tests
• Winners only promoted to scaling

2. Scaling Campaign - CBO

• Mix of Broad + Interest + Lookalike
• 3–5 creative clusters
• Daily budget growth
• Stable signals
• Minimal edits

3. Retargeting Campaign - ABO or CBO (small budget)

• Remarketing windows
• Warm audiences
• Low spend, high efficiency

The “When to Switch” Rule (Memorize This)

Switch from ABO → CBO when:

• you have 2–5 stable creative winners
• your creative fatigue is predictable
• your audience portfolio has proven segments
• you want smoother ROAS
• you’re scaling past $300–$500/day

Stay in ABO when:

• you are testing new creatives
• you need fairness between angles
• your product is niche
• your account has low signal volume
• your CVR is inconsistent

Common Mistakes (2025)

❌ Using CBO for creative testing

CBO will always pick a winner too early.

❌ Scaling with ABO

Volatility will spike, and creative fatigue hits harder.

❌ Too many ad sets in CBO

CBO needs clarity, not chaos.

❌ Mixing weak creatives in CBO

Poor creatives drag down the entire campaign.

Which One Should YOU Use? (Simple Answer)

If you’re testing → ABO

If you’re scaling → CBO

If you’re running both → your structure is correct.

In 2025, it's no longer “ABO vs CBO.”
It’s ABO first, CBO next.
Sequential, not competitive.