Scenario modeling for private funds: A forecasting framework

What is scenario modeling for private funds?

Scenario modeling is a strategic discipline used in portfolio management to make forward-looking capital allocation and risk management decisions for private funds. It is the practice of creating multiple possible futures for a fund by adjusting key variables and assumptions to understand their potential impact on performance. This process moves beyond simple forecasting by allowing you to stress-test your fund’s strategy against a range of outcomes, external factors, and future events.

By modeling different possibilities for factors like exit valuations, follow-on investment rates, and capital deployment pace, you can see how each choice affects critical fund metrics. These metrics include total value to paid-in (TVPI), a type of multiple on invested capital (MOIC), and internal rate of return (IRR). Venture capital (VC)-oriented models may also track ownership at exit and dilution across rounds. Ultimately, scenario modeling provides a data-driven framework for managing the entire fund lifecycle, from initial portfolio construction to final exit.

Why scenario modeling is an important tool for fund managers

As a fund manager, you have a fiduciary responsibility to your limited partners (LPs), a duty underscored by recent SEC rules designed to protect investors in private funds. Robust scenario modeling provides a defensible, data-driven rationale for your strategic choices, which is a cornerstone of responsible stewardship of your LPs’ capital. It allows you to anticipate challenges, identify opportunities, and manage your portfolio with greater precision. Clear separation of construction assumptions and forecasting scenarios improves auditability.

This proactive approach also strengthens LP relations. A well-constructed model helps you build trust and confidently answer tough questions about your reserve strategy and performance expectations, which is a core part of the fund forecasting discipline.

• Informed decision-making process: You can test the forecasted impact of a capital allocation choice before committing funds. For example, you can model whether making a large follow-on investment (which could be structured as a co-investment) in one company or reserving that capital for two new deals will generate a better return for the fund.

• Strategic planning and alignment: Modeling helps you confirm that your investment pace and reserve strategy align with your fund’s investment thesis. It also helps you adhere to the promises made to your LPs in the limited partnership agreement (LPA).

• Enhanced LP communication: You can move beyond static quarterly financial reporting by presenting LPs with dynamic, forward-looking analysis. This demonstrates a sophisticated approach to managing their capital and builds confidence in your strategy.

Scenario modeling vs. scenario analysis vs. scenario planning

While the terms scenario modeling, scenario analysis, and scenario planning are often used interchangeably in private investment contexts, there are important differences between them. Understanding these distinctions is essential for investors, fund managers, and analysts seeking to make more informed, strategic decisions.

• Scenario modeling is about creating and quantifying possible scenarios and potential outcomes. It’s the process of building dynamic financial models that can generate outputs under a range of different assumptions and hypothetical situations—hence “scenarios.”

• Scenario analysis is about interpreting and using those quantified future scenarios to make better investment decisions. It’s an evaluative process, focused on understanding the implications, potential risks, and probabilities associated with each scenario generated.

• Scenario planning is focused on exploring and preparing for a range of future environments that could impact the fund or its portfolio. You may develop structured narratives about possible future situations that encompass qualitative and quantitative factors.

Scenario modeling vs. waterfall modeling

It’s common for fund managers to confuse scenario modeling with waterfall modeling, but they serve two distinct functions. Understanding the difference is key to demonstrating deep industry expertise. Scenario modeling is a forward-looking, strategic tool that you can use to forecast overall fund performance under various conditions.

Waterfall modeling, on the other hand, is a precise calculation tool, often executed using dedicated waterfall modeling software. You use it at the time of a liquidity event to perform a waterfall analysis and determine exactly how to distribute proceeds to LPs and the general partner (GP) according to the LPA.

(For PE and PE‑backed companies that need precise distribution calculations, Carta offers a dedicated waterfall modeling solution that integrates directly with company cap tables.)

Build your forecasting model: From inputs to stress tests

The following framework will guide you through applying scenario modeling from the earliest stages of fund construction all the way to your final exit, helping you evaluate various business exit strategies.

Step 1: Define your fund’s core assumptions and variables

The first step is to establish the foundational inputs for your fund model. These are the fixed parameters and key drivers that will shape your fund's financial future and serve as the basis for all your various scenarios.

Your core assumptions and variables, which are important for portfolio valuation, should include:

• Fund size

• Management fees and fund expenses

• Carried interest structure

• Recycling provisions

• Fund term and investment period

• Target initial check size

• Projected number of portfolio companies (portcos)

• Follow-on investment rate and ownership targets

• Expected exit timing and multiples

Step 2: Translate construction inputs into a deploy-and-reserves forecast

Next, you’ll model your initial portfolio construction based on your fund’s thesis. This involves projecting how you will deploy capital over the investment period, which helps visualize the fund's expected J-curve. The J-curve is a common pattern in PE where a fund has negative returns in its early years before investments mature and generate positive returns. While J‑curve dynamics are common in private funds, shape varies by strategy and market conditions.

A key part of this step is building a reserve strategy for follow-on rounds. This plan should account for exercising your pro rata rights to maintain ownership in your best-performing companies. It should also include stress-testing for potential down-round or bridge financing scenarios. This is an increasingly common pain point for managers who make assumptions without accurate data, especially as market conditions force companies to seek alternative funding. In fact, as of Q2 2025, more VC cash is going to bridge rounds, with the share of capital from these rounds jumping to 16.6% from 11.8% the previous year.

Step 3: Stress-test your model against multiple outcomes: Best, base, and worst cases

With your base model in place, you can now apply a best-case, base-case, and worst-case framework to your fund-level outcomes. This is a form of stress testing that prepares you for a range of market conditions and helps benchmark portfolio performance, often using metrics like public market equivalent (PME).

Here are some examples for each scenario forecasting model:

• Best-case scenario: This model might assume early, high-multiple exits on your investments and a low portco failure rate. It represents an optimistic but plausible outcome.

• Base-case scenario: This model reflects a possible outcome that aligns with your initial fund thesis and historical data for your target market size. It’s the most likely path your fund will take if your assumptions hold true.

• Worst-case scenario: This model prepares you for adversity, assuming a high portco failure rate and delayed exits—a crucial simulation for funds that invested when capital deployment was twice the long-term annual average and valuations were at a peak.

A key part of stress-testing your fund is modeling the financial impact of different exit events. How does an early, high-multiple exit compare to a later, more modest one, especially when the market for VC exits has seen a downward trend in volume and aggregate value since 2023. 

To help you quantify these possibilities and understand their effect on returns, you can download our free exit simulation template to model the effects of common term sheet provisions and assess potential liquidation outcomes.

Free exit simulation template

Download Carta’s free exit simulator tool to model your potential exit scenarios.

Download the template

The limits of spreadsheet-based fund modeling

For years, spreadsheets have been the default tool for financial modeling, including the creation of pro forma financial statements. However, for the complex and high-stakes world of fund management, they present significant limitations that can frustrate even the most detail-oriented chief financial officer (CFO) or controller. Spreadsheets are inherently static and disconnected from live data, forcing you to manually update inputs and check for errors.

This operational drag keeps fund professionals buried in administrative work instead of focusing on strategy, a common pain point for many finance teams. As funds grow, so does the number of relationships they have to manage. For instance, while a median fund under $10 million has 26 LPs, the median LP count for a fund over $250 million is four times higher at 104, dramatically increasing the administrative workload.

Moving from static models to dynamic fund strategy with Carta Fund Forecasting

Purpose-built scenario modeling software like Carta Fund Forecasting resolves the time-consuming limitations of spreadsheets and elevates the CFO’s role from operational to strategic. Instead of a static file, you get a dynamic model that integrates directly with your fund’s general ledger in Carta Fund Administration and your portcos’ ownership data from Carta's cap table software.

This live connection, a core feature of modern fund forecasting software, allows you to compare forecasted performance against actuals in real time, optimize reserves with confidence, and run complex scenario simulations in minutes, not weeks.

For Lauren DeLuca, co-founder and GP at Motivate Ventures, this was a clear advantage. “Running a $40 million fund on Excel just did not seem sustainable,” she says, adding that Fund Forecasting “was light years ahead of our prior Excel-based solution, or anything we had seen in the market.”

For emerging managers, a dedicated tool can be even more transformative: Sophia Amoruso, founder and managing partner of Trust Fund, finds that legacy tools are cumbersome and require extensive existing knowledge of the “complexities of fund construction.” Fund Forecasting provides a guided experience that helps her build a market-ready fund model, answering key questions about reserves, recycling, and market assumptions that would inevitably come up in fundraising conversations.

Request a demo to see how you can move from static spreadsheets to a dynamic fund strategy.

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Frequently asked questions about fund scenario modeling

What is an example of scenario modeling for a VC fund?

A GP could model two scenarios for a portco: one with a modest exit, such as a merger or acquisition, in two years, and another that requires a follow-on investment to pursue a much larger exit in five years, showing the impact of each path on the fund's TVPI and IRR.

How often should you update your fund model?

When using spreadsheets, financial models are often updated quarterly to account for new data. In fact, VCs typically report back quarterly to their LPs on the current state of their portfolio investments, a practice that sets a clear industry benchmark.

Can scenario modeling predict my fund’s IRR?

Scenario modeling provides a range of probable outcomes based on your assumptions, not a guaranteed prediction. This allows you to understand sensitivities and make more informed, defensible decisions about your fund's strategy, backed by audit-ready valuations.