Five trends shaping asset allocation in the core DC menu
Defined contribution plans have become a central pillar of the American retirement system, and the asset allocation underlying their main menu is evolving in a way that investment professionals should not ignore. As target-date funds continue to absorb a growing share of plan assets, core menu allocations are becoming increasingly concentrated in US large-cap equities, with the bias toward growth increasing, while fixed income diversification remains limited.
Based on a decade of 401(k) plan data, this analysis examines the changing composition of core menu allocations. full research was recently released through the DCIIA Center for Retirement Research.
Given the growing importance of defined contribution (DC) plans as the primary retirement savings vehicle for American workers, we think there are five notable trends that investment professionals need to be aware of.
1. Target-date funds (TDFs) are taking over
Default investments, particularly TDFs, continue to capture a growing share of plan assets. With assets in excess of $4 trillion, TDFs have emerged as the dominant default investment option in DC plans, significantly exceeding assets in the other two “qualified” options, which include balanced funds and managed accounts. Consensus estimates suggest TDFs hold about 40% of DC assets today and this could grow to more than 50% by 2030.(1).
The impact of TDF increases has interesting implications for the absolute dollar in traditional core menu funds (think non-default investments) and depends on how the total size of the DC market evolves and whether other default alternatives gain acceptance in the future. For example, Cerulli (2025) estimates that total DC assets could grow from $13.6 trillion in 2024 to $19.3 trillion by 2030. Therefore, even if TDFs continue to gather assets, core menu assets may remain flat, or even turn net positive, especially if managed accounts and other default investment structures that build portfolios leveraging the core menu continue to gain traction.
2. The dominance of US large-cap equities is increasing
Among non-default options, US large-cap equities account for the largest share in the main menu allocation, and this share has increased over time, likely reflecting the strong recent performance of US large-cap stocks.
The weightings of the respective US market-cap groups (large, mid and small) are somewhat surprising, especially when viewed against US or global equity market capitalisations. For example, US large-cap equities hold about four to five times more assets in the core menu than US mid-cap and small-cap equities, even though mid-cap and small-cap equities represent a larger share of total market capitalization (about 16 and 25 times more, respectively). This difference suggests that menu availability, rather than market size, plays an important role in shaping allocation.
3. Growth Trumps Value: :
While US large-cap growth funds are slightly more prevalent than US large-cap value funds on the main menu, they have more than twice as many assets, and the share of their allocation has increased over the past decade. The growth allocation also exceeds other US equity styles, although the difference diminishes at smaller capitalization levels.
This increasing growth bias is consistent with the strong recent performance of growth stocks, but it also increases the risk of style rotation risk if market leadership shifts toward value.
4. Limited fixed income depth in core menu
While options for equities, particularly US equities, are abundant, there is generally a relative lack of diversification options within fixed income in the main menu. For example, while there are typically about 12 equity options available in the core menu, the average 401(k) plan in our study had only about 4.5 fixed income funds, primarily a single cash option and two US intermediate bond funds.
If more DC participants decide to remain in the plan during retirement, fixed income is likely to become increasingly important, as older investors select more conservative portfolios. In our view, this limited change in fixed-income offerings to the main menu over the past decade creates a gap that plan sponsors will need to address.
5. Big plans are more basic
Larger DC schemes offer less diversification than smaller schemes and, as a result, allocate a greater share of assets to more traditional asset classes. This is a somewhat surprising finding, given that larger plans are generally more familiar with the potential benefits of alternative investments, especially those that sponsor defined benefit plans. In theory, larger plans should have greater access to specialized investment options, including private assets, than smaller plans. How this apparent disconnect develops remains to be seen.
Overall, these trends suggest that asset allocation within the DC core menu is shaped not only by deliberate portfolio construction, but also by default, availability, and plan design choices. For investment professionals, understanding how those forces interact is very important as DC plans continue to play a larger role in retirement savings.
(1) Cerulli (2025)
