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Lead’s Checks capabilities let you offer two primary check flows to your end-users: depositing checks and writing checks. Both flows use the X9 file standard — an electronic check format that includes front and back check images along with structured payment data — and route through the Federal Reserve (Fed).
Lead processes all checks via X9 files. There is no API-based check submission.

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Key Terminology

The table below defines the core terms used throughout these guides.

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Write a Check Flow

The Write a Check flow begins when your customer writes a check and gives it to a recipient. The recipient deposits it at another financial institution, which submits the check to the Fed. The Fed delivers it to Lead as an incoming X9 file.
NoteLead does not provide check printing services. Partners are expected to use their own check printing vendor.
Flow SummaryYour customer writes a check → The recipient deposits it at their bank → The receiving bank sends an X9 file to the Fed → The Fed delivers the X9 file to Lead → Lead routes it to you → Lead debits the customer account.

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Returns

A return occurs when you determine that an incoming check must not be honored. To return a check, submit an outgoing X9 file containing the return entries. This follows the same path as the Deposit a Check flow. Common return reasons include:
  • Check details do not match the outstanding check registry
  • Check has already been redeemed (duplicate presentment)
  • Suspected fraud
  • Account closed or insufficient funds
When handling a return, you have the following options:
  • Correct the check details and post to the customer account
  • Make a balance adjustment on the customer account
  • Submit an X9 return file to Lead (standard return)
  • Initiate a late check return by contacting Lead directly
TimingSubmit standard check returns within 24 hours of settlement. Returns initiated after this window are considered late and require direct coordination with Lead’s operations team.

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Deposit a Check Flow

The Deposit a Check flow begins when your customer deposits a check — typically by photographing it in your mobile app using Remote Deposit Capture (RDC). You send Lead an X9 file, Lead submits it to the Fed, and Lead credits funds to your customer.
Flow SummaryYour customer photographs the check → You validate and process the check → You send an X9 file to Lead → Lead checks your daily limit → Lead submits the X9 file to the Fed → The Fed sends an acknowledgement (ACK) → Lead credits the customer FBO → Funds settle at the Fed.
Funds AvailabilityFunds become immediately available for spend once Lead credits the Customer FBO. Lead notifies you in advance of any change to this policy.

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Validation and Fraud Controls

Lead acts as a pass-through in the Deposit a Check flow. You are responsible for all check losses. Build robust pre-submission controls appropriate for your risk appetite before going live.

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Returns from the Paying Bank

After Lead submits a check to the Fed and the Fed delivers it to the paying bank, the paying bank may return the check — for example, if the account is closed or fraud is detected. There are two ways a return reaches you:
  • The paying bank submits an X9 return file to the Fed. The Fed routes it to Lead, who forwards it to you via the Write a Check flow.
  • The paying bank contacts Lead’s operations team directly, outside of the Fed. Lead’s team opens a case and contacts you as needed.
If you absorb the loss or charge it back to your customer, that is an internal funds movement in your system. To formally return a check, submit an outgoing X9 return file to Lead.

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Additional Resources