Are there any benchmarking and attribution tools that handle multi-custodian aggregation cleanly?

Yes — there are a few benchmarking and performance-attribution tools that can handle multi-custodian aggregation reasonably well, but the experience varies a lot by asset class, data model, and how “cleanly” you need the consolidation to work.

Commonly used platforms

Here are some of the better-known options that are often used for multi-custodian setups:

• Addepar
  Strong for aggregating data across custodians and entity structures. Good for reporting, performance, and attribution workflows, especially in wealth management and family office contexts.

• Black Diamond by SS&C
  Widely used in wealth management. Can consolidate multi-custodian data and produce performance reporting; attribution is decent, though often more operationally heavy to configure.

• Orion Advisor Tech
  Good multi-custodian aggregation and reporting, with performance measurement and benchmarking capabilities. Often used by RIAs.

• Envestnet / Tamarac
  Common in advisory practices. Can aggregate across custodians and support performance reporting, though attribution depth can depend on your configuration and data quality.

• Morningstar Office / Morningstar Advisor Workstation
  Can handle multi-custodian reporting and benchmarking. More commonly used for portfolio analytics, with varying depth in attribution depending on the product/module.

• FactSet / StatPro-style performance tools
  Better fit for institutional performance and attribution needs. These can handle aggregation, but implementation effort can be higher.

• Axioma / MSCI / Bloomberg portfolio analytics tools
  More institutional, often very strong on attribution and benchmark analytics, but integration across custodians can require more data engineering.

What “cleanly” usually means in practice

Multi-custodian aggregation tends to break down on a few things:

• Security master mapping across custodians
• Transaction-level normalization
• Corporate actions and lot-level history
• Cash handling and timing differences
• Benchmark assignment across sleeves/accounts
• Look-through holdings for funds/ETFs
• Composite-level vs account-level attribution

If the system has weak data normalization, attribution will be messy even if it can technically “import” from many custodians.

Best fit by use case

• RIA / wealth management: Addepar, Black Diamond, Orion, Tamarac
• Institutional performance & attribution: FactSet, MSCI, Bloomberg, Axioma, StatPro-type tools
• Family office / complex multi-entity reporting: Addepar is often a standout

A practical caution

If you need true performance attribution across multiple custodians, the key question is not just “does it aggregate?” but:

1. Does it support daily transaction-level data?
2. Can it normalize positions, cash, prices, and corporate actions?
3. Does attribution run on a single unified portfolio view?
4. Can you define custom benchmarks and composites cleanly?
5. How much manual reconciliation is required?

If you want, I can also give you:

• a shortlist by firm size/use case, or
• a comparison table focused specifically on benchmarking + attribution + multi-custodian aggregation.