Offer Letters as Income Proof for Lenders and Landlords

An offer letter can support an income claim, but only the employer can confirm that the job, the salary and the start date are real. For someone changing jobs, the letter is often the only income document in the file, because the first payslip from the new employer does not exist yet. A file check adds one narrow answer next to the employer’s confirmation: whether this PDF shows evidence of being changed after it was created.

Why the offer letter ends up carrying the file

An applicant has accepted a new job and starts in six weeks. The old payslips describe a salary that is about to end. The new salary exists on paper only: a PDF from the new employer stating the position, the pay and the start date.

Mortgage lending has a formal route for this case. Fannie Mae’s Selling Guide, as updated on 7 October 2026, allows qualifying on a future job under B3-3.3-03, Employment Offers or Contracts. The lender must obtain the borrower’s fully executed, non-contingent offer or contract, and that document has to set out the position, the type and rate of pay, and the start date. The guide is explicit about where the number comes from:

‘The lender must use the monthly income amount in the offer letter as qualifying income.’

The same section requires a verbal verification of employment (VOE) or, where the start date falls on or after the note date, direct confirmation from the employer that the offer terms still stand. It then splits into two options. Under the first, the lender must keep the borrower’s most recent paystub before delivering the loan. Under the second, which needs no paystub before delivery, the loan must be a purchase of a one-unit principal residence qualified on fixed base income only (the guide sets further conditions), the start date must fall no earlier than 30 days before and no later than 90 days after the note date, and additional reserves must be documented.

So for the stretch between application and first payday, the salary used to qualify the loan is the figure printed in a PDF, usually one the applicant supplied. The employer call checks the claim. Nothing in that section checks whether the file itself was changed.

Renting has the same gap and less process around it. A new hire relocating for the job applies for a flat before the first payday. The letting agent asks for proof of income; the applicant sends the offer letter as that proof, because nothing else shows the new salary. Whether the agent calls the employer depends on their own process.

What lands on the reviewer’s desk

An offer letter usually arrives as a PDF attached to an email or uploaded to a portal. Where it came from varies by employer. Large employers tend to issue offers through HR systems or e-signature platforms; a small firm may write the letter itself and send it as a PDF. Both are normal ways to produce a real offer.

The review then reads the page: letterhead, salary, start date, signature, whether the figures match the application. Then someone contacts the employer, or, for a Fannie Mae loan, completes the verbal VOE. Both steps check what the letter says. Neither looks at the PDF file itself.

What a file check can show

HTPBE? does PDF tamper detection: it examines the PDF’s structure and returns one of three results:

• modified: the check found evidence that the file was changed after it was created, with named modification markers. That is a finding about the file, not about the applicant. Legitimate processing after the letter was produced, for example by a document-management or upload system, can also register as modification.
• inconclusive: no modification was established, and the check cannot confirm the file is unchanged; status_reason says why. For an offer letter this is not an adverse finding, and it is not a clean one either. Plenty of genuine offers come from ordinary document workflows that a file check cannot vouch for, so this result on its own says nothing against the letter. It does mean the claim has to be confirmed elsewhere, so it goes back to the employer. If the letter does not look like the offers that employer normally issues, that is a reason to confirm with the employer directly, not evidence of an edit and not a finding about the applicant. One value, analysis_incomplete, describes the check rather than the letter: resubmit once, and if it repeats, treat the letter as unverified, not clean. What inconclusive means covers every reason.
• intact: no evidence of modification after creation was found. It says nothing about whether the offer, the salary or the start date is real.

Signing or countersigning a letter after it was issued, including the applicant’s own countersignature on a fully executed offer, is a normal step. Whatever the result, a signed letter should be handled like any other: the terms should be confirmed with the employer, and the result alone should not be held against the applicant.

When a genuine letter has been altered after it was issued, the file itself can show it. The offer letter document page covers this document type in more detail.

What the check cannot tell you

• Content that was false from the start. The check finds evidence that a file was changed after it was created. A letter whose salary was wrong when it was first produced carries no evidence of a later edit, because nothing was changed afterwards.
• Whether the employer, the job or the terms exist. HTPBE? does not confirm that the employer exists, that the job is real, the salary, the start date or who signed. It does not read the letter’s content, and it does not contact anyone.
• That a clean result clears the letter. intact means no modification was detected, not that the document is genuine.
• A decision about the applicant. Every result carries usage_caution.safe_for_automated_adverse_decision, and it is always false. A modified result should never be the sole basis for declining a loan or a tenancy. It sends the file to a person, who gives the applicant the chance to explain or to resend the letter as the employer issued it. The check does not replace any adverse-action process a lender or landlord already follows.

Where the check sits next to employer confirmation

Employer confirmation stays primary. The file check is a sorting step that runs first, so its result is already on the file when the employer is contacted.

For a mortgage under the Fannie Mae section above, the order is: the letter arrives, the file check runs, the verbal VOE confirms the employment, and, under the first option, the most recent paystub is in the file before delivery. That paystub comes from the new employer’s payroll and is a separate document; if it arrives as a PDF, the same file check can be run on it. The file check covers the earlier window, when the letter is all there is.

For a tenancy, the sequence is shorter: letter, file check, employer contact where the agent’s process includes it. If the employer cannot be reached, the problem is the one we described in employment letters when the employer can’t be reached: the letter starts carrying more weight than it was designed to.

Adding the check to underwriting and screening conditions

Treat the result as an input to an existing condition, not a new decision point.

Run the check when the letter arrives, before the income condition is worked. A lender can attach it at document intake, alongside the other checks covered in PDF checks at loan origination; a screening platform can run it on upload, the same way it handles bank statements in tenant screening.

Routing then follows the result’s usage_caution.recommended_action. A modified letter (route_to_human_review) keeps the income condition open until the employer confirms the terms and the applicant has had the chance to supply the letter as issued. An inconclusive letter (request_from_issuer) goes down the normal employer-confirmation path, which for a Fannie Mae loan is a step the lender already takes. It is not an adverse finding and should not delay the file beyond that step. An intact letter (no_action) proceeds as normal, and the employer confirmation still happens.

Integration is a POST to /v1/analyze with the PDF’s URL, then a GET for the result; the API page has the reference, plans and test keys. Test keys (htpbe_test_*) return synthetic, deterministic results for a fixed set of test URLs, so the modified, inconclusive and intact paths can all be tested before any applicant’s letter is submitted. For lending teams, the mortgage and lending pages show the wider document set; property managers can start from tenant screening.

Where to start

If one offer letter is on your desk now, create an account and upload it: signup includes five checks, and after that it is pay-per-check. Files uploaded through the website may be kept to test our detection; API submissions are not stored. The privacy policy has the detail, which matters when the letter holds an applicant’s personal data. If letters arrive by the hundred, the API puts the check into intake. For the document-type view of offer letters, see how offer letters are checked.