Policies and AML questionnaires rarely sink a bank partnership. Two industry voices, and the record since Synapse, show that money flows, current financials and ownership records are where founders get caught out.

Most founders prepare for sponsor bank due diligence as if it were an exam on policy. They polish the AML manual, fill in the questionnaire and wait. Then the bank asks a different question: where is the money right now, and can you prove it?

So we asked industry leaders one question: what did your sponsor bank or banking partner ask for in its most recent due diligence that surprised you, and how would you tell other founders to prepare? We wanted tactical guidance, not checklists. Two respondents answered, and their replies point to the same lesson. Sponsor bank due diligence now tests evidence, not paperwork.

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Why sponsor bank due diligence got tougher

The shift has a clear starting point. Synapse, the middleware firm between fintech apps and their partner banks, filed for bankruptcy in April 2024. Its ledgers then failed to match the money the banks held, and tens of millions of dollars in customer funds could not be traced. Since then, banks have tightened contracts and demanded far more transparency, American Banker reported in November 2025.

Regulators pushed the same way. In June 2024, the Federal Reserve ordered Evolve Bank & Trust to overhaul risk management for its fintech partnerships. A month later, the Fed, FDIC and OCC issued a joint statement on deposit products sold through third parties. As a result, sponsor bank due diligence moved from a one-off onboarding step to a standing check. For the wider picture, see our roundup on what embedded finance looks like after the launch.

The money flow is where preparation breaks

Our first respondent works with founders on their books, and he sees the same pattern repeat.

“Most founders expect the compliance questionnaire to be the tough part. In my experience, the financial records cause far more surprises. Teams usually know roughly how to answer the policy and AML questions. What blindsides them is the request for their latest monthly financials, plus a full explanation of how money moves, including where customer funds sit at every stage. Each step in that flow has to be backed by documents.

That’s where I see preparation break down most. My advice is to keep your financials and supporting documents reconciled and reviewed all the time, so you’re ready for questions whenever they come. The founders who can produce current numbers fastest are the ones who can stand behind them.”

Abhinav Gupta, Founder, Profitjets

His point matches what banks publish. Synctera, a BaaS platform that matches fintechs with sponsor banks, lists the documents requested in sponsor bank due diligence. The list starts with a funds flow showing how money moves between the company, the bank and its customers. It also includes two years of financial statements, three-year projections and three months of bank statements, which show cash on hand and spending to date.

Ledger access and daily reconciliation

The bar has risen since Synapse. Patrick Slain, director of fintech at Stearns Bank, told American Banker that banks should receive partners’ ledger data every day. In his view, a bank should be able to rebuild the ledger and run the programme itself if the fintech disappears.

For founders, that changes the task. Sponsor bank due diligence now asks whether the bank can check the numbers without you. Therefore, a monthly close that runs weeks late is a warning sign. Likewise, daily reconciliation, a break log and read-only data access are becoming standard terms.

Ownership and local presence come up early

Ownership questions arrive almost as fast. Synctera says banks generally want every investor holding 10% or more listed on the cap table, including large SAFE holders. Our second respondent described similar pressure from a European bank.

“In our experience with Danish bank onboarding, what surprises founders is how much clarity the bank wants on ownership, business activities and ties to Denmark. If an international founder can’t show a local address, a director or some operational presence, the application can stall.

Get clear records of your business structure, ownership chain and any local presence together before you apply. Treat that paperwork as part of the first application, not something to pull together only when the bank asks.”

Dora Bloom, Chief Revenue Officer, iotum

Her answer concerns a business account in Denmark rather than a BaaS programme. Even so, the lesson carries over to sponsor bank due diligence. EU anti-money laundering law already requires banks to identify beneficial owners, and the new EU Anti-Money Laundering Regulation applies from 10 July 2027. A current ownership record, covered in our roundup on beneficial ownership rules, makes each review faster. Founders often meet these questions first in a second country, as our piece on what breaks first in a cross-border expansion showed.

Regulators eased, but banks did not

Some US pressure has lifted, and several sponsor bank consent orders ended in 2025 and 2026. However, enforcement has not stopped. In April 2026, the OCC signed a consent order against Community Federal Savings Bank, the sponsor behind Wise’s US dollar accounts and Crypto.com’s prepaid card. The regulator found its controls were not “commensurate with its risk and growth,” American Banker reported.

Consequently, sponsor bank due diligence on fintechs keeps returning to transaction monitoring, customer checks and independent testing. Slain also said banks should approve partners’ BSA/AML policies and expect regular independent audits.

How to prepare for sponsor bank due diligence

Taken together, the answers suggest a short order of work. First, draw a funds flow for each product, showing which account holds money at each step and where each reconciliation happens. Next, close the books monthly and keep a rolling cash forecast ready, because banks now test runway as well as compliance. Then reconcile daily and log every break, its cause and its fix.

Beyond that, keep a standing data room with the ownership chart, cap table, licences, AML policies, audit findings and complaints log, each with a named owner. That way, the next round of sponsor bank due diligence becomes a refresh rather than a rebuild. Finally, if you are switching banks, prepare a straight answer on why, because the bank will ask.

What to watch next

Several signals will shape sponsor bank due diligence in 2027. First, watch whether the FDIC revives its proposed custodial account rule, which would require banks to reconcile owner records daily. Also watch whether more consent orders end, and whether new ones follow the Community Federal pattern. In Europe, the single AML rulebook from July 2027 will bring ownership checks into line across member states.

Above all, founders should treat sponsor bank due diligence as an ongoing test of evidence. The questionnaire is the easy part. The money flow, and the records behind it, decide whether the partnership lasts.

FintechBits covers payments, banking and fintech developments for readers in the US and UK. This article is for information only and is not financial or legal advice. Views expressed are those of the FintechBits editorial team.