Building a BMO positive pay file from your check register
Positive pay is the check-fraud control most BMO business customers turn on once they start writing more than a handful of checks. The mechanics are the same as at any bank: each time you cut checks, you send BMO a list of what you issued. When a check hits your account, the bank matches it against your list. If the serial number, amount, or payee does not line up, the item is flagged as an exception and held for you to pay or return. The piece that trips people up is producing the upload file in the layout BMO expects, because no common accounting package writes that file for you.
This page covers where positive pay lives inside BMO's business banking, what is publicly known about the file BMO Harris accepts, and how to generate a matching file from a CSV or Excel register without buying installed software.
Where positive pay sits in BMO's business banking
For U.S. commercial accounts (the former BMO Harris franchise), positive pay is delivered through Online Banking for Business, BMO's treasury and cash-management portal. The check issue file you build is not emailed or pasted into a form. It is uploaded through the File Transfer Facility (FTF), which you reach under the Account Information area of Online Banking for Business. You select Send File, point it at your issue file, and transmit. BMO also offers ACH Positive Pay (also called ACH filters or blocks), a separate control that screens electronic debits by company ID rather than checks. They are different products with different files, so confirm which one you are enrolling in.
If your account was opened on the Canadian side of BMO, the cash-management portal and file specification differ from the U.S. setup. The advice below about getting the spec from your treasury contact still holds, but do not assume the U.S. layout applies.
What the BMO check issue file looks like
Some BMO Harris check issue setups use a comma-separated text file saved with a .TXT extension rather than a fixed-width or .CSV file, though the authoritative layout is the one BMO gives you for your account. A typical issue file is a flat list of the checks you wrote, one record per check, and at minimum carries the data the bank needs to match an item:
- Account number the checks are drawn on
- Check (serial) number
- Check amount
- Issue date
- Payee name, when you run payee-name positive pay
- An item type or void indicator on some configurations
That is the general shape. The exact column order, the date format, whether the amount carries a decimal point or implied cents, how voids are marked, and whether a header or trailer row is required are details BMO sets per customer. We are not going to print a column-by-column map here, because an issue file that is one field out of order, or formats the date the wrong way, gets rejected on upload or, worse, fails to match good checks. The authoritative layout is the one BMO gives you.
Get the spec from BMO, then match it
When BMO enrolls you in positive pay, your treasury management or implementation contact provides a file specification document for your account. Ask for it by name: the check issue file format or check issue file specification for Online Banking for Business. It will tell you the field order, the delimiter, the date format, and how to handle voids and a header row, if any. If you cannot find it, your relationship manager or BMO's treasury support line can resend it. Do not reverse-engineer the format from a sample someone else used. Small differences between accounts and between the U.S. and Canadian platforms are common.
Once you have that spec, the task is purely mechanical: take the check data you already have in QuickBooks, Xero, Sage, or a spreadsheet, and reshape it into BMO's columns and order. QuickBooks is worth calling out because many BMO customers run it and expect an export button. QuickBooks does not write positive pay files in any edition. Desktop and Online both stop at a generic register or transaction export, so the reformatting step is on you regardless of which accounting system you use.
Build the file for free with PositivePayMaker
PositivePayMaker is a free, browser-based tool that turns a check register exported as CSV or Excel into a bank-ready positive pay file. It runs entirely in your browser. Your check numbers, amounts, and payee names are processed on your own computer and never get uploaded to a server, which matters when the data is account numbers and dollar figures.
Because the published BMO Harris layout is a comma-separated .TXT file rather than a fixed published standard like Chase's or Huntington's, the right approach is the custom format builder. You set the columns to match the order on your BMO spec, choose comma delimiters, set the date format BMO wants, and save it as a reusable layout. From then on, every export drops into the same shape. If your spec is close to a plain CSV, one of the generic presets may get you most of the way before you fine-tune. After you generate a file, run it through the built-in validator to catch malformed rows before you ever open the File Transfer Facility.
Always verify the first file with the bank
Treat your first BMO upload as a test. Generate the file, then either run a small batch through the FTF and confirm BMO accepted and parsed it, or send a sample to your treasury contact for review before you rely on it. Watch for the usual mismatches: a date format BMO does not expect, amounts with or without decimals, leading zeros stripped from check numbers, or an extra header row. Once one real file clears cleanly, the layout is locked in and later files are routine. Spend the time on the first one.
When a paid tool makes sense instead
A free browser tool covers most small and mid-size check volumes. If you are at higher volume, want a desktop app wired directly into your accounting data, or need a vendor to maintain hundreds of bank templates for you, paid options exist and may be worth the cost. Big Red Consulting's PositivePay File Creator is Windows-only and runs about $119 the first year then $99 per year; the QuickBooks Online edition needs Excel installed. Treasury Software's Bank Positive Pay is an installed Windows product, roughly $29.95 to $89.95 per month, and ships with 350-plus bank layouts. MoneyThumb and ProperSoft also sell paid desktop converters. For producing an occasional BMO check issue file from a register you already keep, a free client-side tool usually does the job; the paid products earn their keep on volume, automation, and breadth of supported banks.