Investing in infrastructure: the capital stack

The infrastructure capital stack is evolving rapidly across equity, debt and fund finance. 

Equity: concentration at the top, opportunity in the middle

On the equity side, the market is split. Deals above $500m accounted for 98% of deal value in H1 2026, up from 93% in 2025 and 87% the year before.¹ That concentration is being reinforced by GP consolidation – headlined by BlackRock’s c.$12.5bn acquisition of Global Infrastructure Partners in 2024, which created a $170bn platform spanning 100 countries.²

Alongside outright acquisitions, GP stake transactions are emerging as a second route into manager economics. Passive interests in management companies give investors exposure to long-dated fee streams and carried interest. Infrastructure managers are particularly attractive targets, because their fee bases are more durable and their fundraising has held up better than most private markets strategies. These are some of the most bespoke transactions. How you value the interest, what governance the incoming investor gets, and how they realise value on exit all need to be negotiated from scratch, particularly where the manager wants to keep operational control.

As deal sizes grow and platforms consolidate, we have seen a parallel market in minority and non-controlling equity stakes develop. Not every investor needs (or wants) to be the controlling sponsor. For those seeking exposure to infrastructure assets without the operational responsibilities of a controlling position, acquiring a minority interest in a platform or project offers a route into the asset class at the investment level – this then requires careful structuring of the acquisition, negotiating governance and information rights, designing the holding and tax structure, and securing exit protections. 

Infrastructure secondaries have also emerged as a fast-growing segment of the broader market. Fundraising for dedicated infrastructure secondaries vehicles reached a record $11.5bn in 2025, more than double the previous year. Investor appetite has broadened in step, with 21% of investors surveyed considering an allocation to secondaries in 2025, against 9% a year earlier.³ Both LP-led portfolio sales and GP-led continuation vehicles have increased in volume, driven by investors’ need for liquidity in a higher-rate environment and by managers’ desire to hold their best-performing assets for longer. Infrastructure is particularly well suited to these structures due to the long duration and contracted cashflows of the underlying assets. These deals require the alignment of incoming and rolling investors on valuation methodology, the negotiation of governance rights within continuation vehicles, and the management of potential conflicts of interest where the GP sits on both sides of the deal. 

More broadly, consolidation has two further consequences that matter for investment professionals. First, it is changing how assets are exited - secondary buyouts overtook trade sales for the first time in several years in 2025, rising from 33% of exits in 2021 to 53%, and reaching 58% in H1 2026.⁴ Second, it is creating counter-cyclical opportunity in the mid-market. We are seeing the same consolidation that concentrates capital at the top of the market also producing spin-outs and team moves at the bottom, rebuilding the deal flow that consolidation removes. 

Debt: the bankability signal

The growth of private debt in infrastructure is more than a lending story. When debt capital enters a segment of the market, it signals that lenders see cashflows they can underwrite – contracted revenue, predictable demand, or both. Debt arrival is, in effect, a bankability indicator.

The numbers are striking. Private debt deployed nearly $300bn into infrastructure between 2021 and 2025, rising from $49bn to $75bn annually. Its share of total deal count nearly doubled, from 14% to 24% and reached 27% in the first half of 2026.⁵ We expect that share to continue growing. That growth is also driving demand for new fund formation, with private credit managers establishing dedicated infrastructure debt units and a growing number of infrastructure credit vehicles reaching close.⁶

From 2021 to July 2026, roughly 88% of private debt deals financed greenfield construction, not operational assets.⁷ The pattern is visible across segments. EV charging now has the highest private debt penetration of any identified subsegment at roughly 35%, whilst battery storage is close behind, with tolling agreements providing the predictable revenue that merchant-only projects could not.⁸ Tracking the source of debt and where it sits is a helpful tool to assess where a sector is on its maturity curve.

Fund finance

As the capital mix has become more sophisticated, so have the structures around it. Fund finance has moved from the margins of infrastructure into a central role, and this is where much of the structuring complexity now sits.

Subscription lines can accelerate deployment, and NAV facilities unlock liquidity from operational portfolios by lending against asset values, giving infrastructure sponsors a route to distributions or reinvestment without an exit. Co-investment arrangements bring in additional capital alongside the main fund. Layered on top of project-level debt, these arrangements allow sponsors to calibrate leverage at both fund and asset level, and they help explain why sponsor-to-sponsor transactions and continuation vehicles have become so popular, as compared to trade sales. 

For investors and their advisers, this layering also introduces a set of questions that sit at the intersection of fund structuring, tax, and transaction execution – for example: how leverage at fund level interacts with project-level debt covenants; how continuation vehicles are priced and governed; how co-investment economics are allocated; and how cross-border holding structures are designed for tax efficiency. As the sector moves from core into core-plus and value-add strategies, we are seeing management incentive plans, governance frameworks, and carried interest structures – all familiar from a private equity context – move into the mainstream in infrastructure transactions. Much of this work sits squarely at the investment level, upstream of the operational management of the underlying asset.

Tax structuring remains important. Holding structures often need to accommodate investors from multiple jurisdictions, each with different tax profiles and reporting preferences. This cannot always be done within a single vehicle, and the balancing act between flexibility and complexity can be a difficult one. 

Cross-border deployment adds a further dimension. Pillar Two's global minimum tax rules are reshaping how infrastructure holding structures are designed. There can also be a divergence between approaches to, for example, interest deductibility, and the regime in the jurisdiction where the capital is sourced can often be quite different from the requirements of the investee jurisdiction. 

While such jurisdictions welcome investment, tax authorities – particularly in an infrastructure context – are alive to the cross-border element of such investment and as a matter of policy will apply withholding tax to dividends and interest paid to certain jurisdictions.   

The next section of this report considers what gets an asset to the point where capital can be deployed, and where much of infrastructure’s value now lies: Investing in infrastructure: navigating complexity and dependencies.