Income document red flags underwriters catch in seconds — and how to pre-screen for them.

The employment letter, the most recent pay stub, and the T4 or year-to-date figures are supposed to tell the same story from three angles — and when they don't, that's the first thing an experienced underwriter's eye goes to.

• →Job title or employer name that doesn't match across the letter, pay stub, and application.
• →Dates that don't line up — a letter dated before a start date it references, or a pay stub period that doesn't match the letter's stated hire date.
• →Year-to-date math that doesn't reconcile against the stated pay rate and the number of pay periods elapsed — a quick calculation an underwriter runs almost reflexively.

None of these individually proves anything is wrong, but each one is exactly the kind of detail that turns a same-day review into a conditions request.

A borrower still inside a probationary period reads as unconfirmed employment to most lenders, regardless of how secure the job actually feels to the borrower — it's a timing issue, not a character judgment, and it needs to be flagged upfront rather than discovered mid-review.

Variable income — commission, bonus, overtime, or self-employment — creates a different trap: a broker who takes the most recent, strongest month or year at face value instead of properly averaging it across a representative period is setting up a number the underwriter will simply recalculate downward, often after asking for more history than was originally submitted.

A pay stub or letter that's aged past a lender's freshness window doesn't just get flagged for replacement — it reads as a file that wasn't assembled with the underwriter's timeline in mind, which invites closer scrutiny of everything else in the package.

Outstanding CRA tax arrears on a Notice of Assessment is a more serious version of the same signal: it's an unresolved obligation the underwriter has to factor into the debt picture, and surfacing it proactively, with a payment plan or resolution timeline attached, reads far better than having it discovered during review.

An employment letter that reads as obviously generic — no letterhead, generic phrasing, missing a direct contact for verification — doesn't automatically get rejected, but it does routinely trigger a direct verification call to the employer, which adds a full round to the file's timeline for something a properly formatted letter would have avoided.

A letter on company letterhead, with a named, reachable contact and specific figures that match the rest of the package, is one of the cheapest ways to remove an entire category of underwriter follow-up.

Before a file goes out, run every income document through the same short check: do the name, employer, and dates match across every document; does the year-to-date math reconcile against the stated pay rate; is every document inside the lender's freshness window; is there a probationary period, and has it been flagged; and is variable income backed by a proper multi-period average rather than the single best month.

It takes a few focused minutes on a straightforward file, longer on a self-employed or variable-income one — but it's reliably faster than the round of conditions it prevents. The Pre-Underwriting File Review Checklist turns this into a repeatable list rather than something you have to remember every time, and the same document logic extends to condition-family issues covered in the most common underwriting conditions on Canadian files. Treadstone's Engage AI mortgage underwriting, currently in early access via waitlist, runs this exact pre-screen automatically for brokers who want it done in seconds rather than minutes.