What Is a Fractional CMO and What Do They Do?

Introduction

Founders and CEOs know the challenge: growth stalls, fundraising looms, and the marketing team is running at full capacity without clear strategic direction. At this stage, the real gap is not in running more campaigns; it is in having senior marketing leadership. Yet for many companies, bringing on a full-time Chief Marketing Officer is costly, time-consuming, and often premature.

That’s where a fractional CMO comes in.

A fractional CMO is an experienced marketing leader who works with your business part-time or on a contract basis, providing executive-level strategy and oversight without the cost and long-term commitment of a full-time hire. Increasingly, funds and founders are turning to this model to unlock growth and accelerate portfolio value.

What Is a Fractional CMO?

A fractional CMO (Chief Marketing Officer) is a senior executive who provides strategic marketing leadership on a flexible basis. Instead of joining as a permanent, full-time hire, they work fractionally, often a set number of days per week or month, bringing the same expertise and decision-making power as a traditional CMO.

Unlike agencies that focus on execution, or consultants who deliver narrow recommendations, a fractional CMO embeds into your leadership team. They sit at the executive table, set strategy, and ensure alignment between marketing, sales, and revenue.

Key differences:

  • Fractional CMO vs Full-Time CMO: same caliber of expertise, but flexible engagement and dramatically lower cost.
  • Fractional CMO vs Interim CMO: interim roles are temporary replacements, often full-time; fractional roles are ongoing, part-time leadership engagements.

In practice: A startup preparing for a Series A might bring on a fractional CMO for 15–20 hours a week to build a growth strategy, guide the team, and represent marketing in board discussions.

What Does a Fractional CMO Do?

The exact scope depends on your company stage, industry, and growth priorities, but typically a fractional CMO will:

Set Growth Strategy

  • Define the marketing vision aligned with business goals.
  • Build a go-to-market strategy for new products or markets.
  • Create integrated demand generation plans that drive pipeline.

Lead and Align Teams

  • Provide leadership to in-house marketers, agencies, or freelancers.
  • Clarify roles, KPIs, and accountability.
  • Bridge the gap between marketing, sales, and product.

Enable Fundraising and Board Reporting

  • Develop the marketing narrative for investors.
  • Translate performance metrics into board-level insights.
  • Position the company competitively in the market.

Accelerate Revenue and Scale

  • Identify levers for growth: acquisition, activation, retention.
  • Optimize channel mix and marketing spend.
  • Build systems and reporting for predictable revenue.

Understanding Different Marketing Leadership Approaches

When considering fractional marketing leadership, it’s important to understand the distinction between different types of marketing expertise:

Strategic CMO Leadership

  • Overall marketing strategy and vision
  • Cross-functional alignment with sales, product, and executive teams
  • Brand positioning and messaging architecture
  • Marketing organization design and team leadership

Performance Marketing

  • Paid advertising and digital acquisition channels
  • Conversion optimization and funnel management
  • Data-driven campaign optimization
  • ROI measurement and attribution modeling

Brand Marketing

  • Brand identity and creative strategy
  • Content marketing and storytelling
  • PR and communications strategy
  • Brand awareness and perception management

A fractional CMO typically operates at the strategic level, coordinating and directing both performance and brand marketing efforts while ensuring they align with overall business objectives.

Benefits of Hiring a Fractional CMO

For many founders, the choice is not between a fractional CMO and a full-time CMO. It is between getting senior marketing leadership now or waiting until the business can afford it. The costs of waiting are real: missed growth opportunities, inefficient spend, and stalled fundraising.

Top benefits include:

  • Executive-level impact without full-time cost.
  • Faster speed to contribution: fractional leaders integrate quickly and deliver immediate value.
  • Flexibility: scale hours and scope as company needs evolve.
  • Access to talent from top global brands. Many fractional CMOs come with pedigrees from companies like Apple, Nike, or Google, networks most startups could not normally reach.

When Should a Company Hire a Fractional CMO?

Timing is often the difference between unlocking growth and missing an opportunity. Signs that it is time to bring on a fractional CMO include:

  • Preparing for fundraising, especially Series A or Series B.
  • Growth has plateaued and the team lacks a clear marketing strategy.
  • Expanding into new markets or launching a new product.
  • The CEO, COO, or founder is carrying too much of the marketing burden.

From a fund perspective, fractional CMOs can be deployed across a portfolio to address gaps quickly and create value without the delay of lengthy executive searches.

Fractional CMO vs Alternatives

Fractional CMO vs Marketing Agency

  • Agencies execute campaigns but do not typically own strategy.
  • A fractional CMO ensures the strategy is right, then directs agencies and teams effectively.

Fractional CMO vs Interim CMO

  • Interim CMOs are full-time temporary replacements.
  • Fractional CMOs are part-time, flexible, and often long-term partners.

Fractional CMO vs Consultant

  • Consultants advise but rarely implement.
  • Fractional CMOs embed into the leadership team and drive execution.

Comparison Table:

Role

Scope

Engagement Type

Best For

Fractional CMO

Strategy + Oversight

Part-time, ongoing

Scaling companies, portfolio value creation

Interim CMO

Temporary Replacement

Full-time, short-term

Backfilling a vacancy

Marketing Agency

Campaign Execution

Retainer or project

Tactical delivery under guidance

Consultant

Advice and recommendations

Short-term, advisory

Point solutions, specific challenges

Why Choose Size.vc for Fractional CMO Support

Most providers of fractional CMO services are either individual consultants or agencies trying to repackage themselves. Size.vc is different.

  • Deep alignment with funds and founders.
  • Access to executives who have led marketing at world-class companies.
  • A network built to place leaders quickly and effectively, across portfolios.

[Insert Case Study: Startup growth through fractional marketing leadership.]

Work With a Fractional CMO Today

The right marketing leadership can be the difference between stalled growth and accelerated scale. If your company is ready for a fractional CMO, don’t wait.

Book a Call today to connect with our team and get matched with the right executive to power your growth.

Frequently Asked Questions

What is a fractional CMO and what do they do? A fractional CMO is a senior marketing executive who works with companies part-time to set strategy, lead teams, and accelerate growth. They provide executive-level leadership without the full-time cost.

Is a fractional CMO worth it for startups? Yes. For startups preparing to raise capital, expand, or accelerate growth, a fractional CMO provides senior leadership faster and more affordably than a full-time hire.

Where can I find a fractional CMO? Fractional CMOs can be found through networks like Size.vc, which specializes in connecting founders and funds with vetted executive talent from world-class companies.