What a Good Tax Preparer Should Catch Before You File

A good tax preparer does more than record the documents you provide and generate a return. The role requires reviewing submissions, identifying gaps or inconsistencies, and asking follow-up questions to achieve a more accurate filing. That review process is what separates document processing from professional tax preparation.

The return reports what happened during the prior year. That is compliance work. But compliance done well requires judgment, and the judgment shows up in the questions a preparer asks before the return is filed. Missing a single document can shift a tax liability by tens of thousands of dollars. Filing with incomplete information results in IRS notices, amended returns, and, in some cases, avoidable penalties and interest.

This article covers what a careful preparer reviews, what kinds of errors the review catches, and how to evaluate whether your current preparer is performing that work.

What Separates Document Processing from Return Review

Entering data means taking the documents a client provides, recording the numbers, and producing the return. Reviewing a return means examining the full picture and asking whether the information is complete. The second step is where professional judgment changes outcomes.

Consider a client who owns a home and submits a mortgage interest statement but no property tax records. These two expenses typically appear together. When one is present and the other is missing, that gap should raise a question before filing. A preparer working at the data-entry level files the return as it arrives. A preparer reviewing the return contacts the client about the missing records, because property taxes are a deductible expense and omitting them reduces the return’s accuracy.

This kind of review does not require advisory work or strategic planning. It requires attention to patterns and experience to recognize what a complete return should include for a given client’s situation.

What a Careful Preparer Reviews Before Filing

An experienced preparer recognizes patterns in the documents they receive. When those patterns break or a piece is missing, the preparer investigates before completing the return. This applies across income levels and entity types, and it covers several specific areas.

Income reporting gaps. A business owner who had a strong revenue year but whose 1099s do not reflect the full amount of income received may have unreported payments. The preparer should compare total deposits or reported revenue against the 1099s provided and ask about any material difference. Under the IRS Small Business Tax Guide, the 2026 information reporting threshold requires third-party platforms to issue a 1099-K when payments exceed $2,000. Business owners receiving payments through digital platforms may have new reporting obligations they are not yet tracking.

Incomplete deduction documentation. A client claiming home office expenses without providing utility bills, insurance records, or square footage measurements has submitted an incomplete picture. A careful preparer requests supporting records rather than omitting the deduction entirely or estimating the amount. The difference between claiming a documented deduction and skipping it because the paperwork was not requested can represent several thousand dollars on the return.

Outstanding or corrected forms. Tax forms from employers, brokerages, and financial institutions sometimes arrive in stages. Clients frequently submit their initial set of documents in February without realizing that a corrected 1099 or a K-1 from a partnership is still pending. Asking whether all expected documents have been received prevents filing a return that will need to be amended weeks later.

S corporation document alignment. For S corporation owners, the review includes verifying that the K-1 aligns with the corporate return and that compensation reported on the W-2 is consistent with payroll processing during the year.

Discrepancies between these documents are common and can create IRS matching issues if they reach the agency without correction. Business owners who want to understand how their compensation and entity structure affect their tax position may need a separate planning conversation, but the document alignment check is part of preparation.

What Happens When a Missing Document Changes the Liability

Missing or incomplete documents do not just affect accuracy. They can significantly affect tax liability, and correcting the error after filing adds time, complexity, and potential penalties.

One client brought documents that produced a calculated liability of approximately $150,000. The numbers appeared consistent on the surface. After reviewing the information and asking additional questions, we identified that a tax document from the client’s employer was incomplete. Once the full document was obtained, the corrected return reduced the liability by roughly $70,000.

That correction came from preparation, not from planning or strategy. The result followed because the preparer identified a gap instead of accepting the documents at face value.

When errors are not caught before filing, the correction process is more expensive. The IRS receives copies of most tax documents issued to you, including W-2s, 1099s, and K-1s. If your return does not match what the IRS has on file, you will receive a notice. Correcting the error requires an amended return using Form 1040-X, which takes eight to sixteen weeks to process. If the amendment increases what you owe, interest accrues from the original due date, and penalties may apply depending on the size and nature of the underpayment.

Questions To Ask Before Filing

A tax return should begin with questions.

Before your return is prepared, your accountant should ask what changed, what was earned, what was paid, and what may affect how your return is filed. That is where good tax preparation starts. The goal is not to give tax advice before the numbers are reviewed. The goal is to ensure your return accurately reflects what happened during the year and that nothing important is missed before it is filed.

Many filing errors occur because the return was built solely on documents. A W-2, a 1099, or a prior year return only tells part of the story. A tax preparer still needs to ask the right questions to catch missing income, overlooked deductions, filing changes, and payment issues before those mistakes turn into notices, penalties, or amended returns.

If your accountant is preparing your return, these are the questions that should be asked before filing.

Questions Your Accountant Should Ask About Income

• Did you receive income outside your main job or primary business 

• Did you earn freelance, consulting, or contract income that may not be on a W-2 

• Did you receive 1099 income from side work or self-employment 

• Did you collect rental income, short-term rental income, or property distributions 

• Did you receive dividends, interest, or capital gains from investments

• Did you sell stock, cryptocurrency, real estate, or other assets during the year 

• Did you take money out of retirement, brokerage, or savings accounts

  
  

Questions Your Accountant Should Ask About Life Changes

• Did you buy or sell a home 

• Did you move to another state 

• Did you get married, divorced, or legally separated 

• Did you have a child, adopt, or add a dependent to your household 

• Did a dependent stop qualifying during the year 

• Did you start, close, or restructure a business

  
  

Questions Your Accountant Should Ask About Tax Payments

• Did you make quarterly estimated tax payments to the IRS 

• Did you make state estimated tax payments 

• Do you have records of every payment made during the year 

• Did your withholding change at any point during the year 

• Did you apply last year’s refund to this year’s taxes 

• Have you received any IRS or state tax notices since your last return was filed

  
  

Questions Your Accountant Should Ask About Deductions and Reporting

• Did you pay mortgage interest or property taxes 

• Did you make charitable contributions 

• Did you pay large medical expenses 

• Did you contribute to an HSA 

• Did you make retirement contributions outside of payroll 

• Did you pay for childcare, dependent care, or education expenses 

• Did you make large business purchases or pay contractors that may need to be reported

A tax return is only as accurate as the questions asked before it is filed. Good accountants do more than collect documents. They ask the questions that catch what paperwork alone does not. That is often the difference between filing a return that is simply submitted and filing one that is complete.

Where Preparation Ends and Planning Begins

Preparation documents what has already happened. It does not restructure decisions or create forward-looking strategies. The return records income earned, deductions taken, and payments made during the prior year.

Compliance done well still requires professional skill. Classifying income correctly, applying the right filing status, identifying eligible credits, and verifying that all required schedules are included are all part of the preparation work. A mistake in any of these areas can generate an IRS notice, an underpayment, or a missed refund.

The distinction worth understanding is between preparation and tax planning. Planning is forward-looking. It involves projecting the current-year tax liability, modeling retirement contributions, evaluating the entity structure, and adjusting compensation and estimated payments while there is still time to affect the outcome. That work happens during the year, not at filing time. If you are making business decisions in 2026 without knowing their tax implications, you may benefit from a planning engagement with a different scope and timeline. Year-end decisions that affect your return are covered in more detail in our year-end tax planning guide.

How to Evaluate Whether Your Preparer Reviews or Processes

Several indicators distinguish a preparer who reviews your return from one who processes your documents with minimal scrutiny. These are observable patterns you can assess based on your recent filing experience.

Follow-up questions. If you submitted documents and received a completed return without a single clarifying question, the return may have been processed rather than reviewed. Most returns contain at least one area where a question would improve accuracy. Preparers who file without asking have either assumed the information is complete or are not checking for gaps.

Contextual explanations. A preparer who reviews the return should flag items that seem unusual, whether that is a higher-than-expected liability, an unusually large deduction, or a credit the client did not anticipate. If the return arrives without context or explanation, the client is left to interpret the results without guidance.

Document hold requests. A preparer who asks you to wait before filing because a document is still outstanding is demonstrating awareness of what the return should contain. Filing immediately with whatever is provided may prioritize speed over accuracy, and the cost of that trade-off shows up when the IRS sends a notice months later.

Year-over-year comparison. A preparer who compares the current return against the prior year’s filing looks for unexplained shifts. If income dropped 30% without a corresponding change in business activity, that warrants a question. If a recurring deduction disappears, that warrants a question. Comparing returns across years is a standard review practice that catches omissions a single-year review might miss.

Frequently Asked Questions

Should my tax preparer ask me questions before filing?

Yes. Asking follow-up questions is part of careful preparation. If your preparer reviews the documents you submit and identifies gaps, missing forms, or inconsistencies, raising those questions before filing produces a more accurate return. A preparer who files without any clarifying contact may be processing documents rather than reviewing them.

What is the difference between tax preparation and tax planning?

Tax preparation reports what happened during the prior year by compiling income, deductions, and credits into a return filed with the IRS. Tax planning is forward-looking and takes place during the current year. It involves income timing, compensation structure analysis, entity evaluation, estimated payment recalculation, and retirement contribution strategy. These are separate services with different scopes, different timing, and different engagement structures.

Can a missed document on my return cause problems with the IRS?

It can. The IRS receives copies of most tax documents issued to you, including W-2s, 1099s, and K-1s. When your return does not match their records, you receive a notice requesting an explanation or additional payment. Correcting the error requires filing an amended return using Form 1040-X, which takes eight to sixteen weeks to process. If the correction increases your liability, interest accrues from the original due date.

How do I know if my return was reviewed or just processed?

A reviewed return typically involves follow-up questions, an explanation of anything unusual, a check for document completeness, and a comparison against the prior year’s filing. If the return arrived without questions, context, or a request to verify outstanding documents, it may have been processed as submitted rather than reviewed for completeness.

What does it cost to fix an error after a return has been filed?

The cost depends on the nature of the error. Filing an amended return (Form 1040-X) takes eight to sixteen weeks to process and may incur professional fees for the preparer’s time to rework the return. If the amendment increases your tax liability, the IRS charges interest from the original due date. Underpayment penalties may also apply. These costs are avoidable when the error is caught during the original preparation.

DesCPA provides tax preparation and planning services for small business owners, S corporation owners, and high-earning professionals. If you want a preparer who reviews your return carefully and asks the right questions before filing, schedule a consultation to discuss your situation.