Capital Stack Optimization: How Founders Are Blending Debt, Equity, and Secondaries in 2026

In 2026, founders are rethinking how they structure capital, blending equity, debt, and secondaries to maximize flexibility and control.

Venture and growth investors deployed $425 billion into more than 24,000 private companies in 2025, up 30% year-over-year.¹ Yet capital is concentrating into fewer companies, with larger checks flowing primarily to later-stage and AI-driven startups.² For most founders, this shift is increasing the need for a more deliberate and diversified capital strategy.

The Evolving Capital Stack

The capital stack remains the foundation of how companies are financed, a hierarchy of capital ranked from lowest risk (and lowest cost) to highest risk (and highest return). At its core, this reflects how founders structure debt vs equity in a more dynamic financing environment.

Top to Bottom: Lowest Risk → Highest Risk

• Senior Debt (First Lien)

  First in line for repayment and typically secured by company assets. This remains the lowest-cost form of capital and a cornerstone of private credit.

  
  

• Unitranche Debt

  A blended structure combining senior and subordinated debt into a single facility, embedding multiple risk layers within one instrument.

  
  

• Second Lien Debt

  Subordinate to first lien but still secured, offering higher returns in exchange for increased risk and often used to extend leverage.

  
  

• Mezzanine Debt

  Typically unsecured or lightly secured, often incorporating PIK interest, warrants, or equity kickers, bridging debt and equity.

  
  

• Preferred Equity

  Senior to common equity with structured returns or preferential payouts, often used as a hybrid solution.

  
  

• Common Equity

  The most junior layer, last in line for repayment but with the highest upside.

While this framework remains intact, how founders use the capital stack is evolving.

Debt use cases are expanding (see our prior piece on private credit as a strategic lever). Founders have more flexible, non-dilutive funding options available in market, particularly in capital-efficient growth models.³ For many companies, particularly SaaS and subscription businesses, venture debt, revenue-based financing, and other ARR term loans may provide capital without immediate dilution or loss of control.⁴

Secondaries: Parallel to the Stack

Secondaries are often discussed alongside equity and debt, but they are fundamentally different. They are not part of the capital stack because they do not introduce new capital into the business.

Instead, they provide liquidity for shareholders and may reshape ownership.

As companies stay private longer, ownership structures are becoming more complex. Early investors and employees hold significant stakes with limited liquidity, while newer investors enter with different expectations and time horizons.

In our thought piece, Understanding secondaries in investment portfolios, we talk about how secondaries have emerged in response to this imbalance. Secondary transaction volumes have grown, and founder/shareholder liquidity programs are being set up more regularly now (though still in select companies).

The Real Constraint: Cap Table Gridlock

As capital stacks become more layered, a new constraint is emerging: cap table gridlock.

Complex ownership structures, misaligned incentives, and concentrated early positions can slow or block key decisions, from financings to exits. In many cases, the issue is not access to capital, but friction within the existing ownership base.⁶

This dynamic is increasingly shaping how companies finance themselves.

This is where capital stack optimization becomes less about access to capital, and more about managing ownership complexity.

When equity issuance becomes difficult, whether due to valuation sensitivity, signaling concerns, or lack of stakeholder alignment, debt often becomes the most viable path forward. Unlike equity, debt does not require broad agreement on valuation or ownership dilution, allowing companies to access capital without reopening complex cap table negotiations.

In this context, debt becomes more than a financing tool, it becomes a mechanism for navigating constraint.

Secondaries play a parallel role. By enabling liquidity and rebalancing ownership, they help relieve pressure within the cap table without introducing new primary capital or forcing a primary round repricing. While debt allows companies to continue operating and growing, secondaries help ensure the ownership structure does not become a long-term impediment.

Conclusion: Capital Is No Longer the Only Variable

Optimizing a company’s financial strategy in 2026 requires more than choosing between equity and debt. It requires managing the interaction between capital and ownership.

A more flexible capital stack can reduce dilution and increase optionality. Debt can extend runway when equity markets are constrained. Structured equity can bridge valuation gaps. And secondaries can relieve internal pressure that would otherwise stall decision-making.

But these tools also introduce complexity. Financing decisions are more interdependent, market conditions remain volatile, and stakeholder management has become more demanding.

The environment founders operate in today is structurally different from just a few years ago. Capital is concentrating, rounds are larger, and companies are staying private longer.

Founders who treat the capital stack as only part of the equation, and actively manage their cap tables alongside it, will be best positioned to navigate this next phase of private markets. The most resilient companies won’t be the ones that simply raised the most capital, but the ones that structured it and their ownership most intelligently.

About Axis Group Ventures

Axis Group Ventures is a boutique investment banking and strategic advisory firm. We focus on global debt placement and private market secondaries for venture- and private equity-backed companies. Our firm partners with founders, CFOs, and investors to provide customized capital solutions in the private markets. We leverage deep experience in private credit and a global network of capital providers. Axis Group Ventures’ mission is to bring greater transparency and alignment to complex financing decisions through disciplined, independent advisory and high-touch execution. For more information, visit www.axisgroupventures.com.

Sources:

1. Crunchbase. Global Venture Funding 2025. Crunchbase. https://news.crunchbase.com/venture/funding-data-third-largest-year-2025/

2. Fidelity Private Shares. VC in 2026: What the Latest Data Reveals for Founders. Fidelity Private Shares. https://www.fidelityprivateshares.com/blog/venture-capital-in-2026-what-the-latest-data-reveals-for-founders

3. Crestmont Capital. Revenue-Based Financing Statistics. Crestmont Capital. https://www.crestmontcapital.com/blog/revenue-based-financing-statistics

4. re:cap. Revenue-Based Financing: A Complete Guide. re:cap. https://www.re-cap.com/financing-instruments/revenue-based-financing

5. GHC Funding. Entrepreneurial Finance 2026: Trends Shaping the Year Ahead. GHC Funding. https://ghcfunding.com/2026/blog/entrepreneurial-finance-2026-trends/

6. Fortune. Unicorns Are Flush With Cash and Stuck. Fortune. https://fortune.com/2026/03/20/unicorn-cap-table-gridlock-startup-2026/

Disclosures & Disclaimers

This blog post is provided by Axis Group Ventures for informational and educational purposes only. It does not constitute investment, legal, accounting, or tax advice, and should not be relied upon as such. Nothing contained here should be interpreted as an offer to buy or sell any securities. Any actual offer or solicitation will be made exclusively through formal documentation provided by the relevant issuer or seller.

Axis Group Ventures is not a registered broker-dealer and does not execute, negotiate, or recommend the purchase or sale of securities. Any introductions or private-market support provided by Axis Group Ventures are conducted strictly in an advisory and consulting capacity. Readers should conduct their own due diligence and consult qualified professionals before making any financial decisions.

Investments in private securities involve significant risks, including the potential loss of the entire investment, and are typically illiquid. Past performance does not guarantee future results.