What Triggers Manual Underwriting?

When a loan is submitted, the loan officer runs it through an automated underwriting system. DU and LP analyze hundreds of data points — credit score, income type, debt ratios, assets, LTV, and loan type — against a proprietary risk model and issue a finding. An Approve/Eligible finding means the loan meets automated guidelines and can proceed through normal processing. A Refer or Refer/Caution finding means the system cannot confidently approve the file and it requires a human underwriter.

AUS systems are optimized for typical borrower profiles: W-2 income, 700+ credit, three or more open tradelines, and a straightforward purchase. They are not good at evaluating edge cases. A borrower who paid cash for everything for 20 years and has no credit file presents the AUS with insufficient data to issue an Approve — but is arguably one of the most responsible borrowers in the application pool. AUS Refer findings are a data problem, not always a creditworthiness problem.

Based on 20+ years of originating and underwriting mortgage files, these are the most frequent reasons a file goes to manual review:

1. No traditional credit score or fewer than three active tradelines. DU requires a minimum number of tradelines to run the risk model. Below that threshold, the system issues a Refer. This affects borrowers who avoid credit entirely, immigrants new to the U.S. credit system, and those who have closed old accounts.

2. Recent bankruptcy within the waiting period. An FHA loan filed less than two years after a Chapter 7 discharge, or less than one year into a Chapter 13 repayment plan, requires manual underwriting if the lender will entertain it at all.

3. Mortgage delinquency in the past 12 months. A borrower who missed a mortgage payment within the past year almost always receives a Refer from DU because recent mortgage lates are one of the highest-risk indicators in the model.

4. Debt-to-income ratio at the edge of program limits. A conventional file at 44% DTI that DU will not Approve at 45% must be manually reviewed with compensating factors.

5. Non-traditional or difficult-to-model income. IHSS caregiver income, irregular self-employment, seasonal agricultural income, and non-U.S. income can confuse AUS inputs and produce Refer findings even when the income clearly qualifies.

6. Multiple financed properties at the edge of eligibility. Fannie Mae limits conventional loans to a borrower who owns ten financed properties. At or near that threshold, AUS often returns a Refer that requires manual confirmation of the property count and documentation.

Under FHA manual underwriting, the standard maximum DTI is 31% front-end (housing expense) and 43% back-end (all debts). These are tighter than AUS guidelines, which can approve FHA files at 57% back-end in some scenarios.

Compensating factors allow expansion beyond the standard limits. With one documented compensating factor, FHA allows 37/47. With two, 40/50. The factors must be documented, not just claimed.

The five FHA compensating factors and their documentation requirements:

1. Cash reserves of at least 3 months PITI (12 months for 3-4 unit properties). Documented by 2 months of bank statements showing the balance after closing costs and down payment.

2. Minimal payment shock: the new housing payment does not exceed the current housing expense by more than 5%. Documented by 12 months of canceled rent checks or landlord verification letter plus mortgage statements.

3. No discretionary debt: the borrower pays all credit card balances in full each month. Documented by 12 months of credit card statements showing zero balances carried over.

4. Significant additional income not used in qualifying: overtime, part-time income, or other income sources the borrower receives but which do not meet the continuity requirement. Documented by paystubs and employer letters confirming the income.

5. Residual income: the borrower's monthly income after all debt obligations meets or exceeds the VA regional residual income table for their family size. Documented by the same income verification plus the residual income calculation worksheet.

The critical nuance: a compensating factor is only valid if the documentation for that factor is in the file at submission. Claiming a factor without evidence is not a compensating factor — it is an unsubstantiated assertion, and the underwriter cannot use it.

Automated underwriting evaluates your file through a statistical model. Manual underwriting evaluates your file through a person. That distinction matters more than most loan officers appreciate.

When I was reviewing manual underwriting files from the underwriting desk, the first thing I looked for was whether the file told a coherent story. A borrower with a thin credit file who had never missed a rent payment in eight years, had six months of reserves, and held the same job for four years — that is a strong manual underwriting case even without a credit score. The story is there. The risk is manageable.

The second thing I looked for was whether the loan officer had submitted a narrative. A narrative is not required, but it is one of the most important things a skilled broker can include. A good narrative explains the credit situation, documents the compensating factors, and presents the borrower's history in context rather than forcing the underwriter to reconstruct it from raw documents. Files submitted without narratives take longer and accumulate more conditions because the underwriter must ask for every piece of context that a narrative would have provided upfront.

The third thing I looked at was whether the compensating factors were actually documented or just mentioned. A cover page that says 'borrower has significant reserves' with no bank statements attached is worse than saying nothing — it flags a sloppy submission. A cover page that says 'borrower has 9.2 months of PITI reserves as shown on pages 14-17' is a file that moves cleanly.

Manual underwriting is most often discussed in the FHA context because FHA has a defined compensating factor framework. Conventional loans can also go to manual underwriting, but the structure is less formalized.

For conventional files that DU issues a Refer on, the loan can be submitted to an experienced human underwriter at the lender. There is no explicit 31/43 starting point or formal compensating factor expansion tier system the way FHA has. The underwriter applies judgment within Fannie Mae guidelines and the lender's own overlays.

In practice, this makes conventional manual underwriting more variable and less predictable. A file that would qualify under FHA's explicit 40/50 compensating factor framework might or might not be approved under conventional manual review depending on the lender and underwriter. Most high-DTI or non-standard files are better served by FHA's structured manual underwriting pathway than by attempting conventional manual review.

The exception is VA. VA manual underwriting is actually quite lender-friendly when the residual income calculation is strong. VA focuses on whether the veteran can sustain the housing expense after all other obligations, not just on the DTI percentage. A veteran who exceeds the residual income table by 20% or more has a strong basis for manual approval even at higher DTI ratios.