Customized benchmarks vs. traditional benchmarks: what are the differences, advantages, and risks?
27 JUL, 2026
Benchmark selection is far from a technical afterthought – it shapes how performance is measured, how risk is assessed, and ultimately whether an investment manager can demonstrate genuine value beyond the market. As mandates grow more specialized and client needs more diverse, the debate between traditional, market-cap-weighted benchmarks and customized, mandate-specific alternatives has become increasingly relevant across the industry.
Traditional benchmarks like the S&P 500 or the Bloomberg US Aggregate offer transparency, comparability, and ease of implementation – qualities that make them the default choice for performance reporting and peer comparison. But for portfolios with liability-driven strategies, ESG exclusions, or highly flexible mandates, a standard index can create a dangerous mismatch between beating the benchmark and actually meeting client objectives.
We asked three investment professionals – an asset management CIO, a fund selector, and an investment and asset management specialist – to weigh in on when customization adds real value, and when it introduces more risk than it resolves.
Dimitris Dalipis, Chief Investment Officer, Alpha Trust
For an asset manager, choosing between traditional and customized benchmarks requires balancing two competing priorities: capturing broad market performance versus ensuring you are solving a client’s specific, real-world problems.
Standard benchmarks like the S&P 500 are easy to trade and everyone understands them. But they are one-size-fits-all tools. They can force you to choose between rigid tracking or career-threatening tracking error, even when your client’s specific liabilities, ESG constraints, or risk tolerances dictate a different path. Beating the index can sometimes mean failing your client’s underlying objectives.
Customized benchmarks let you build a framework that fits your client's specific needs perfectly. By tailoring factors, sectors, or cash flow matching, you can close the gap between market performance and client needs – ensuring that your success is defined by the client's actual goals, not an arbitrary market cap index.
The advantage is better accuracy. The risk, however, can be a dangerous cocktail of complexity and complacency. Custom benchmarks can easily suffer from "backtest optimization," where managers engineer past data to look perfect only to watch it crumble in real-time markets. Furthermore, they degrade transparency and introduce higher operational overhead.
So ideally, the framework should be close to something as simple as this: Use traditional benchmarks to gauge raw skill (alpha) in broad markets. Deploy customized benchmarks when your client’s overall profile – from liabilities to unique risk tolerances – is so distinct that standard indexing guarantees misalignment. Customization has strong advantages, but only if you have the operational governance to police its hidden complexity.
Diogo Verde, Fund Selector at Millennium bcp.
From a fund selector's perspective, benchmarks play a critical role because they provide the basis for comparing strategies. Traditional benchmarks remain the most effective tool in this regard, particularly in core asset classes where investors expect managers to operate within a clearly defined opportunity set. Having a widely recognized benchmark for a given segment enhances transparency, facilitates peer comparisons and makes performance attribution meaningful.
That said, customized benchmarks can be appropriate in certain situations. Strategies with highly flexible and unconstrained mandates or total return objectives may not fit neatly into a traditional market index. Similarly, managers incorporating specific ESG exclusions or uncommon sustainability requirements may find that a more customized benchmark better reflects their investable universe.
The main challenge is that customization can reduce comparability across products. In an investment landscape with an ever-growing range of opportunities, investors need to be able to compare and select the best option for their needs. Transparency is essential. Investors should clearly understand why a customized benchmark has been chosen and how it differs from standard market references. At the same time, even customized benchmark strategies can have a reference traditional benchmark for comparison purposes.
Ultimately, traditional benchmarks should remain the default option, especially in core segments, while customized benchmarks should be reserved for cases where they genuinely improve the representation of a strategy's investment objective and constraints.
Zeynep Aslan, Investment and Asset Management Professional
Benchmark selection plays an important role in portfolio governance. It determines how performance is measured, how risk is assessed, and whether an investment manager has created value beyond general market movements.
Traditional benchmarks, such as the S&P 500 or Bloomberg US Aggregate, represent broad markets through standardized and publicly available methodologies. Their main strengths are transparency, comparability, and ease of implementation. They are also widely accepted for performance reporting, fee assessment, and the distinction between active returns and passive market exposure.
Their usefulness becomes more limited when a portfolio has a specialized mandate. A broad index may not adequately reflect an institution’s asset allocation, liability profile, liquidity requirements, or investment restrictions.
| Feature | Traditional Benchmark | Customized Benchmark |
| Objective | Represent a market or asset class | Reflect a specific investment mandate |
| Construction | Defined by an independent provider | Built through index combinations, exclusions, or strategic tilts |
| Flexibility | Limited | Adaptable to portfolio requirements |
| Governance | Straightforward | Requires additional data and oversight |
Customized benchmarks are intended to close this gap. A pension fund may use a liability-based fixed-income benchmark, while an endowment may combine several indices to reflect its exposure to equities, bonds, real estate, and private markets. Sector exclusions or ESG requirements can also be incorporated where relevant.
The greater precision, however, comes with additional risks. A customized benchmark may become difficult to explain, costly to maintain, or too closely aligned with the existing portfolio. Frequent, discretionary changes are particularly problematic, as they can weaken the benchmark’s independence and create the impression that performance standards are being adjusted retrospectively.
A customized approach is most effective when its methodology, review process, and rebalancing rules are established in advance and documented within the Investment Policy Statement. Customization should improve the relevance of performance measurement without compromising consistency or accountability.
