Every held-away account a client mentions — the 401(k) at the old employer, the spouse's brokerage, the trust at another institution — represents assets the advisor can't see, can't plan around, and can't manage. Data aggregation solves this by pulling external account data into the advisor's view. In theory, it's the key to true holistic advice. In practice, the market is in the middle of its most significant disruption in a decade.

The Incumbents and the Disruption

For years, wealth data aggregation meant one thing: screen scraping. Envestnet Yodlee, the dominant provider, built its business on credential-based scraping — logging into financial institutions as the user and extracting account data from the HTML. It worked, after a fashion. It was also fragile (breaks whenever a bank redesigns its website), insecure (requiring clients to share login credentials), and increasingly unwelcome (banks actively blocking scrapers).

The disruption has three vectors. Open banking APIs — driven by the CFPB's Section 1033 rulemaking on consumer data rights — are mandating that financial institutions provide API-based data access. This shifts aggregation from adversarial scraping to authorized API connections: more reliable, more secure, more complete. Akoya, the API network spun out of Fidelity, now connects to thousands of institutions through formal data-sharing agreements rather than screen scraping. Plaid, after its failed $5.3 billion Visa acquisition, doubled down on wealth management use cases — its investments API now serves many of the same aggregation needs with a developer experience the legacy providers never offered.

Screen scraping was a hack that became an industry. Open banking APIs are the industry growing up — but the transition will be messy, and the firms caught mid-migration will feel it.

The transition timeline matters. The CFPB's rulemaking has faced legal challenges and political headwinds, but the direction is irreversible: credential-based scraping is being regulated out of existence, and API-based aggregation is the replacement. Firms building aggregation-dependent workflows (held-away 401(k) management, comprehensive financial planning, prospecting tools) need to ensure their providers are on the right side of this shift.

What Aggregation Enables

When aggregation works, it unlocks capabilities that differentiate modern advisory:

Held-away asset management. The average mass-affluent household holds 40-60% of investable assets outside their primary advisory relationship — mostly in employer retirement plans. Firms like Pontera (formerly FeeX) built entire businesses on managing held-away 401(k)s: the advisor can't custody the assets but can direct the allocation through the plan's interface. This requires reliable, real-time position data — which requires robust aggregation.

Comprehensive planning. A financial plan built on 60% of a client's assets is a partial plan. Aggregation feeds the planning software (eMoney, MoneyGuidePro) with the full picture — enabling accurate retirement projections, tax analyses, and estate planning that account for everything the client owns.

Prospecting and onboarding. Some firms use aggregation during prospecting: "Link your accounts and we'll show you what you're paying in fees across all of them." This transparency play — pioneered by Personal Capital (now Empower) — converts prospects by revealing what their current arrangements cost. It requires aggregation that works on the first try, in front of the prospect, which is the highest-stakes test of reliability.

The Reliability Problem

Here's what vendors don't advertise: aggregation breaks constantly. Industry estimates suggest 10-20% of aggregation connections fail at any given time — expired credentials, multi-factor authentication challenges, institution website changes, API outages. Each failure is a support ticket, a frustrated client, and a gap in the advisor's view.

The best firms manage this operationally rather than technologically. They monitor connection health proactively, reach out to clients before the client notices, and maintain fallback processes (manual statement upload, advisor-assisted reconnection). They also set expectations honestly: aggregation covers 85-90% of institutions reliably, with long-tail gaps at smaller banks, credit unions, and international institutions.

The firms that struggle treat aggregation as a feature that should "just work." It doesn't, and it won't — the underlying data sources are too heterogeneous, the authentication requirements too variable, the institutional incentives too misaligned. Aggregation is an operational capability requiring ongoing investment, not a checkbox on a vendor evaluation.

Selecting an Aggregation Provider

For RIAs evaluating aggregation in 2026, the criteria have shifted. API coverage matters more than institution count — a provider with 5,000 API-connected institutions outperforms one with 12,000 scraped connections. Wealth-specific data quality — cost basis, transaction history, holdings detail, not just balances — separates serious providers from balance-display tools. held-away trading capability (for 401(k) management use cases) is a distinct requirement from data aggregation, and few providers do both well. Security posture — SOC 2 Type II, penetration testing, data retention policies — is non-negotiable now that aggregation handles client credentials at scale.

The market is consolidating around a few winners, but the open-banking transition means today's leader may not be tomorrow's. Firms should prioritize providers investing in API infrastructure over those maintaining scraping operations — and should structure contracts to allow migration as the market evolves.

Aggregation is the plumbing of holistic advice. It's invisible when it works and catastrophic when it doesn't. In 2026, the firms winning on client experience are the ones that treat it as infrastructure worthy of investment, not as a vendor feature to be assumed.