How Many Minor League Baseball Teams Are There in 2025?

By Sarah Miller · April 7, 2029

As of the 2025 season, there are 120 affiliated Minor League Baseball teams in the United States and Canada, organized across six different levels: Triple-A, Double-A, High-A, Single-A, and two levels of Rookie ball.

Understanding Minor League Baseball Structure

Minor League Baseball (MiLB) serves as the developmental system for Major League Baseball (MLB), providing a structured pathway for players to progress from amateur status to the major leagues. Following a significant reorganization by MLB in 2021, the number of affiliated teams was reduced from 160 to 120, streamlining operations and improving player development standards.

This restructuring also standardized facility requirements, travel conditions, and player compensation across leagues.

Key Levels in Minor League Baseball

Triple-A (AAA): The highest level, featuring players closest to MLB readiness.
Double-A (AA): Mid-tier level focusing on advanced development.
High-A: Intermediate level emphasizing skill refinement.
Single-A: Entry-level full-season competition.
Rookie Advanced & Complex Leagues: Short-season or summer leagues for newly drafted players and international signees.

Distribution of Minor League Teams by Level

The 120 affiliated MiLB teams are distributed across five primary classifications. Each classification supports multiple leagues, with each league hosting 6–10 teams. This tiered system ensures progressive player development under MLB oversight.

Classification	Number of Teams	Leagues	Notable Leagues
Triple-A	30	2	International League, Pacific Coast League
Double-A	30	3	Eastern League, Southern League, Texas League
High-A	30	3	Midwest League, Northwest League, South Atlantic League
Single-A	30	3	California League, Carolina League, Florida State League
Rookie	0*	2	Arizona Complex League, Dominican Summer League

Table data source:1, 2

*Note: While over 80 Rookie-level teams exist across the Arizona Complex League and Dominican Summer League, these are not counted in the official 120-team total due to their non-full-season and developmental-complex nature. The 120-team count includes only full-season domestic affiliates.

The table shows an equal distribution of 30 teams at each of the four full-season levels (AAA, AA, High-A, Single-A), reflecting MLB's effort to standardize team numbers and competitive balance. This symmetry simplifies affiliation agreements and scheduling logistics.

Affiliation System Between MLB and MiLB

Each of the 30 MLB franchises controls four full-season minor league affiliates—one at each of the four main levels. This one-to-four model ensures consistent player development pipelines.

How Affiliations Work

MLB teams sign Player Development Contracts (PDCs) with MiLB clubs.
Each affiliate hosts prospects from its parent MLB club.
PDCs typically last four years, renewed automatically under recent rules.
MLB directly funds player salaries, equipment, and travel for all affiliates.

This centralized control enhances operational efficiency and player welfare compared to the pre-2021 decentralized model.

Geographic Distribution and Market Impact

Minor League teams span 43 U.S. states and Puerto Rico, with concentrations in populous regions like California, Texas, and the Southeast. These teams play a vital role in local economies, drawing millions of fans annually.

In 2024, MiLB drew over 40 million fans collectively, demonstrating strong grassroots support despite structural changes.

Frequently Asked Questions About Minor League Baseball Teams

How many minor league baseball teams are there in 2025?

There are 120 affiliated Minor League Baseball teams in 2025, divided equally into 30 teams each at Triple-A, Double-A, High-A, and Single-A levels.

Why did Minor League Baseball reduce to 120 teams?

MLB reduced the number from 160 to 120 in 2021 to improve facility standards, streamline travel, enhance player pay and conditions, and strengthen organizational control over development systems.

Do all 30 MLB teams have their own minor league teams?

Yes, each MLB team operates four full-season minor league affiliates—one at each level: Triple-A, Double-A, High-A, and Single-A—ensuring a complete player development pipeline.

Are Rookie leagues included in the 120-team count?

No, the 120-team count does not include Rookie-level teams in the Arizona Complex League or Dominican Summer League, which consist of additional short-season and international squads outside the full-season affiliate structure.

What is the difference between High-A and Single-A?

High-A (Advanced A) is a step above Single-A (Low-A) in the hierarchy. Players typically spend one season at Single-A before advancing to High-A, where competition is stronger and performance expectations higher.