WorkflowResidential Mortgage & Home Equity Origination

Self-Employed Income Calculation

Self-employed income calculation from the tax returns, every figure traced to its line

An income worksheet in minutes, every figure traced to the return.

See one case, screen by screen ↓
demo91sfor six agents to read 42 pages and fill 19 worksheet lines on the Castellano file
demo31of 31worksheet figures linked to their line on the return
demo1,308.05$ a monthby which the quick estimate at application overstated the qualifying income
target10minfrom a complete income file to a signed worksheet
In short

What is Self-Employed Income Calculation?

Software that turns a self-employed borrower’s tax returns into qualifying monthly income: it reads the personal and business returns, applies the agency cash-flow method with its add-backs and subtractions, and tests trend, liquidity and transcripts. Self-Employed Income Calculation does that with six agents and links every figure on the worksheet to its line on the return.

How to choose AI solutions for lending →

Updated

The problem

Why self-employed income is slow to calculate and easy to get wrong

When a borrower owns a business, nobody hands the underwriter an income figure. It is rebuilt from two years of personal and business returns: ordinary income from the 1120-S, the borrower’s share from the K-1, the W-2 the business paid them, every Schedule C and Schedule E — each with its own add-backs and subtractions, and the one-time gains and short-term notes that have to come out.

Then the judgement calls. Is income stable or declining, and does the year-to-date P&L show the decline has stopped? Were K-1 earnings distributed, or does the business have the liquidity to support them? Does the transcript match the return? By hand that is an hour or more per file, and a small slip in an add-back or a declining-income test is among the most common income defects QC finds.

typical20%of critical mortgage defects are income and employment errors
typical1–6hoursto calculate a self-employed borrower’s income by hand
demo5.4%by which the income moved from the estimate at application on the Castellano file
Where a self-employed file’s minutes goestimated
By hand195 days
With the solution10.5 days
  • Sorting the file and finding each line45 → 0.5 d
  • Filling the cash-flow worksheet60 → 0.5 d
  • Trend, year-to-date P&L and the written analysis30 → 0.5 d
  • K-1 distributions, liquidity and notes payable30 → 0.5 d
  • Matching returns to transcripts15 → 0.5 d
  • Review and signature15 → 8 d

Estimated split for one file with an S corporation, a Schedule C and a rental, by hand and with the solution.

How it works

How an income file moves

Six specialist agents read every return and fill the worksheet line by line; the underwriter decides and signs.

What comes in
Income file in42 pages · returns, K-1s, W-2s, P&L, transcripts
Agents at work
Return readerevery line, cited
Then
Transcript matcher
Cash-flow calculator
Then
Liquidity and distributions checker
Trend and continuance analyst
Then
Conditions and decision writerincome + conditions
A person decides
Underwriterdecides and signs
What comes out
Signed qualifying income
Form 1084 and Form 91, every line sourced
Conditions and loan officer note
One case, step by step

One income file, from complete to signed

Daniel and Lena Castellano are buying 2218 Juniper Hollow Drive in Meridian with a $692,000 conventional loan. He owns 60% of an S corporation, she runs a photography business on Schedule C, and they rent out a condo. Here is their file, screen by screen, in the working solution.

  1. 01Monday morning

    Eight files on her desk, the next one ready

    Priya Raman · Senior underwriter

    Priya opens Income files: eight self-employed and rental borrowers, ranked by what needs a decision. The Castellano file was marked complete on Friday — 42 pages, the 2024 transcript in, 2025 pending. The loan officer’s estimate at application sits beside it: $24,222.17 a month.

  2. 02One click

    “Fill the worksheet” — and the figures land

    Priya Raman · Senior underwriter

    The return pages are on the left and the Form 1084 worksheet in the middle. Each figure glows on its line of the return and flies onto the worksheet while the monthly income meter adds up. The run log beside the work shows each agent as it finishes.

    Transcript matcher: “2024 matches line for line · 2025 no record, filed on extension 14 Sep.”

  3. 031 min 31 s later

    $22,914.12 a month, 31 of 31 figures traced

    The agents

    The last line to land is Lena’s Schedule C depreciation — line 13, $5,600 and $6,100, added back at $487.50 a month. Daniel’s income, Lena’s two-year average and the condo’s +$81.33 total $22,914.12: $1,308.05 below the estimate, DTI 35.71%. A dashed line joins the selected worksheet line to its line on the return.

  4. 04Click any line

    Why it is there — the rule, the line, the arithmetic

    Cash-flow calculator

    Priya clicks “Net gain on sale of equipment”. The note says why it came out: an $18,500 gain from selling a 2019 skid steer and trailer, 1120-S line 4 and Form 4797 Part II, happened once and will not recur. Daniel’s 60% share comes off at $925 a month.

    “B3-3.7-02 · nonrecurring income”

  5. 05Same file

    Form 1084 and Form 91, side by side

    Priya Raman · Senior underwriter

    Every line is also worked the Form 91 way. 18 of 19 lines agree. They differ on notes payable: the lender’s Form 91 rule set subtracts the $30,000 credit line unless the bank’s renewal letter is in the file, and the file has only the CPA’s statement 4. Form 91 gives $21,414.12 and DTI 38.21%. The loan goes to DU, so Form 1084 is used — and one click asks the processor for the renewal letter.

  6. 06Trend

    Declining income, never averaged

    Trend and continuance analyst

    Daniel’s income fell 8.9%, from $240,960 in 2024 to $219,600 in 2025, so 2025 is used alone: $18,300.00 a month instead of the $19,190.00 two-year average. The 2026 P&L through 30 September annualizes to $211,600 of ordinary income, 12.6% above 2025, so the decline has stopped. The written analysis is drafted for Priya to edit and keep.

    Choosing the two-year average is an override — it goes to Marcus Dell for a second review.

  7. 07Liquidity

    K-1 income above distributions, so liquidity is tested

    Liquidity and distributions checker

    Daniel’s 2025 K-1 shows $112,740 of income against $96,000 distributed, 85%. The current ratio is 1.38 — $412,600 of current assets over $298,300 of current liabilities, above the 1.00 threshold — so the K-1 income counts. Schedule L line 17’s $52,000 is split from statement 4: a $30,000 revolving line with Ridgeway Community Bank that renews every April, and $22,000 due on an equipment note. Only the $22,000 is subtracted.

  8. 08Transcripts

    2024 matches; 2025 is not on record yet

    Transcript matcher

    The 2024 transcript matches the return on 6 of 6 lines. For 2025 the IRS answered “no record of return filed” on 8 October — the return was e-filed on extension and accepted on 14 September, and the acknowledgement is in the file. A condition goes to the processor: the 2025 transcript before closing.

  9. 09Decision

    Income by source, DTI, and a note for the loan officer

    Conditions and decision writer

    $18,300.00 from Daniel, $4,532.79 from Lena, $81.33 from the condo. DTI moves from 33.78% at application to 35.71%, ready to resubmit to automated underwriting. Five findings reviewed, no finding overridden, and a plain note to Tyler Brandt drafted — sent only when Priya signs.

  10. 10Signed

    Priya signs the qualifying income

    Priya Raman · Senior underwriter

    $22,914.12 a month. Her figure equals the worksheet, so no second review is needed. She signs, the signature records that she reviewed the income, its sources and the written analysis, Tyler is told the income changed by −5.4%, and the transcript condition goes to Jenna Ortiz.

    “Your figure equals the worksheet. No second review is needed.”

Who it’s for

Built for everyone who touches an income file.

The same Castellano file, seen by the five people who carry it to closing and beyond — what their week looked like, and what it looks like now.

PR
Priya RamanSenior underwriter
Underwriter
Before
Rebuilds qualifying income from two years of personal and business returns by hand — an hour or more per file.
Now
Starts from a filled worksheet with every figure tied to its line, reads the why notes, and signs.
MD
Marcus DellUnderwriting manager
Underwriting manager
Before
Hears about income defects only when QC writes them up, after the loan has closed.
Now
Sees worksheets signed, median minutes, findings by type and every override with its second review.
JO
Jenna OrtizProcessor · conditions and documents
Processor
Before
Is told the file is incomplete, then works out which year is missing.
Now
Gets one named condition — the 2025 transcript, before closing — with the reason attached.
TB
Tyler BrandtLoan officer
Loan officer
Before
Quoted the borrowers from a quick two-year average and learns late that the income moved.
Now
Gets a plain note when income changes by more than 3%: the new figure, why, the new DTI and the open item.
AW
Ana WhitfieldPost-closing quality control
Quality control
Before
Re-underwrites closed loans without the reason behind each adjustment.
Now
Opens the worksheet with the source line, the guide section and the arithmetic for every adjustment.
Built on the engine

6 agents. Each with one job, and hard limits.

Six specialist agents read every return and fill the worksheet line by line; the underwriter decides and signs.

Return reader

Classifies every page of the income file — 1040 and schedules, 1120-S, 1065, 1120, K-1s, W-2s, P&L, leases — and extracts each line used for income with its tax year, page and line.

  • Never infers a figure that is not on the page
  • Cites page and line for every value
  • Marks an unreadable line for a person
Transcript matcher

Compares each return with its IRS transcript line by line, reads e-file acknowledgements and requests a transcript again when the IRS has no record.

  • Never accepts a year without a transcript or proof of filing
  • Raises a condition for the processor when the IRS has no record
Cash-flow calculator

Builds the worksheet in the program’s format — Form 1084 with the Form 91 column for conventional, FHA and VA rules otherwise — and applies the ownership share.

  • Never applies an add-back or subtraction the guide does not list
  • Every figure linked to a line on the return
Trend and continuance analyst

Compares gross receipts, costs, expenses and taxable income by year, reads the year-to-date P&L, business age and ownership, and drafts the written analysis.

  • Never averages two years when income is declining
  • The underwriter owns the final analysis
Liquidity and distributions checker

Tests K-1 income against distributions, computes the current ratio — or the quick ratio for inventory businesses — and separates credit lines that renew from notes that fall due.

  • Never counts K-1 income that was neither distributed nor supported by liquidity
Conditions and decision writer

Sums qualifying income by source, compares it with the estimate, recomputes DTI, prepares the automated underwriting resubmission, writes conditions and the note to the loan officer.

  • Never signs
  • Never changes income after the underwriter signs
Underwriter

Decides and signs; a manager reviews any override. The agents propose; a named person decides.

Ask in plain words

Ask about any figure, in plain words

Underwriters can ask about any figure, finding or document in an income file — or say what to add. Every answer points to its line.

Why is Daniel’s income based on 2025 only?

Because it declined. His W-2 plus his 60% share of the business cash flow was $240,960 in 2024 and $219,600 in 2025, down 8.9%. When income declines, the most recent year is used rather than the two-year average — $18,300.00 a month instead of $19,190.00. The 2026 P&L annualizes to $211,600 of ordinary income, 12.6% above 2025, so the decline has stopped.

Why wasn’t the $30,000 credit line subtracted?

Schedule L line 17 shows $52,000 payable within a year. Statement 4 splits it: a $30,000 revolving line of credit with Ridgeway Community Bank that renews every April, and $22,000 due this year on an equipment note. Lines of credit that roll over regularly do not have to be subtracted (B3-3.7-02), so only the $22,000 is. Subtract all of it and Daniel’s income is $16,800.00 a month, and the file goes to a second review.

Why do Form 1084 and Form 91 come out differently?

On one line only: notes payable. Form 1084 does not subtract the credit line that rolls over, so Daniel is $18,300.00 a month. Your Form 91 rule set subtracts it unless the bank’s renewal letter is in the file, and the file has only the CPA’s statement 4 — so the Form 91 total is $21,414.12, DTI 38.21%. The loan goes to DU, so Form 1084 is used: $22,914.12.

Add a condition for July to September business bank statements

Added: 2026 business bank statements, July to September, for Castellano Landscape Group, Inc., before closing. They confirm the deposits behind the 2026 P&L that the trend analysis relies on. Jenna Ortiz has been asked for them. That makes 2 conditions.

Every screen

The working solution, as it ships.

13 screens from the working solution, on its sample data. Pick one to see it large.

The worksheetThe return on the left, Form 1084 in the middle with the Form 91 column, the monthly income meter, the why note and the run log.
Filling line by lineEach figure glows on its line of the return and lands on the worksheet while the monthly income adds up.
Why a line is thereA one-time equipment gain taken out: the source lines, the arithmetic, the guide section and the agent that filled it.
Form 1084 against Form 91The one line where the two methods differ, the reason, and a button to ask for the bank’s renewal letter.
Income filesEvery self-employed and rental borrower, ranked by what needs a decision, with the estimate beside the calculated income.
Trend and continuanceComparative income analysis by year, the 2026 year to date annualized, the method chosen and the drafted written analysis.
Liquidity and distributionsK-1 income against distributions, the Schedule L balance sheet, the current ratio and notes payable split by statement 4.
Rental incomeThe condo’s Schedule E with its add-backs, the monthly payment from the statement and the checks behind it.
Return against transcriptLine by line for each year used; the 2025 “no record” answer with the e-file acknowledgement beside it.
The income decisionIncome by source, the change from the estimate, DTI before and after, the note to the loan officer and the activity.
Signing the incomeThe underwriter signs the qualifying income; a second review is added only when her figure differs from the worksheet by more than 5% or a finding is overridden.
Income qualityWorksheets signed, median minutes, findings by type, QC income defects and second reviews by underwriter.
Your rulesProgram guides, the Form 91 rule set, declining income, the liquidity test, transcripts and approvers — all settings.
Governance

Built for loan quality: traced, reasoned, signed.

Every figure tied to its lineEach of the worksheet’s figures links to the document, page and line it came from. Click a figure and its line lights up on the return.
Every adjustment names its ruleEach add-back, subtraction and exclusion carries a note with the guide section, both source lines, the arithmetic and the agent that filled it.
The underwriter signs the incomeAgents calculate and recommend. A named underwriter signs, and the signature records that the income, its sources and the written analysis were reviewed.
Overrides get a second reviewWhen the underwriter’s figure differs from the worksheet by more than 5%, or a finding is overridden — averaging a declining year, subtracting a rolling credit line — the underwriting manager reviews before it counts.
No year without its transcriptEvery tax year used for income needs its transcript before closing. A “no record” answer becomes a named condition for the processor, not a silent pass.
Every step on the recordEach agent step and each human decision is on the file’s activity trail. Rule changes in Settings are versioned and dated, and the written analysis is kept with the worksheet.
Configuration

Your credit policy, not ours

The rules every income file is calculated against are settings — changes are versioned, dated and on the audit trail.

SettingDefaultChoose from
Conventional program rulesSelling Guide of 7 Oct 2026Selling Guide of 7 Oct 2026 · Selling Guide of 2 Sep 2026
Form 91 rule set · credit linesBank renewal letter requiredBank renewal letter required · Borrower’s statement accepted
Declining incomeMost recent year onlyMost recent year only · Most recent year, or average with a second review
Written analysis when income declines more than5%Set up or down
Liquidity testCurrent ratio · quick ratio for inventory businessesCurrent ratio · quick ratio for inventory businesses · Quick ratio always · Current ratio always
Liquidity threshold1.001.00 · 1.10 · 1.25
Transcripts for every tax year usedRequired before closingRequired before closing · Required before approval
Tell the loan officer when income moves more than3%1% · 3% · 5%
Connections

Works with the income file you already collect

Personal tax returns1040s with Schedules C, E, F and SE
Business returns and K-1s1065, 1120, 1120-S with Schedules L and M-1
Year-to-date P&L and balance sheetread against the trend and the liquidity test
IRS transcriptsForm 4506-C requests and e-file acknowledgements
Agency guides and your overlaysSelling Guide, HUD Handbook 4000.1, VA Pamphlet 26-7
Automated underwritingresubmitted at the signed income
What it changes

The difference, in numbers.

Every figure is labelled: a target the solution is built to, an estimate, a typical published result, or a proven one.

target
10min
from a complete income file to a signed worksheet
By hand1–6 hours
With agents≈ 10 min
target
100%
of worksheet figures linked to a line on the return
31 of 31 figures
on the hero file
typical
20%
of critical mortgage defects are income and employment
1 in 5 defects
ACES, Q1 2026

“demo” = seen in the working solution, on its sample loan file · “target” = the design goal, measured in the live solution · “estimated” = our estimate · “typical” = published figures (ACES Mortgage QC Industry Trends Q1 2026 via National Mortgage News — income and employment 20.07% of critical defects; vendor-published manual calculation times of one to six hours). People, companies, borrowers and properties named on this page are fictional — characters and sample data in the working solution.

Questions

What underwriting teams ask us.

What is self-employed income calculation software?

Software that turns a self-employed borrower’s tax returns into qualifying monthly income: it reads the personal and business returns, applies the agency cash-flow method with its add-backs and subtractions, and tests trend, liquidity and transcripts. Self-Employed Income Calculation does that with six agents and links every figure on the worksheet to its line on the return.

Which cash-flow methods does it use?

For conventional loans it fills the Form 1084 worksheet and works every line the Form 91 way in a column beside it, marking any line where the two differ. FHA files follow HUD Handbook 4000.1 and VA files the Lenders Handbook, chapter 4. The guide releases in use are settings.

How does it handle declining income?

When income falls from one year to the next, the trend and continuance analyst uses the most recent year rather than the two-year average, reads the year-to-date P&L to see whether the decline has stopped, and drafts a written analysis for the underwriter to edit and keep. Choosing the average anyway goes to a second review.

Does it count K-1 income above distributions?

Only when the business can support it. If K-1 income is above the distributions received, the liquidity and distributions checker computes the current ratio — or the quick ratio for inventory businesses — from Schedule L and the latest balance sheet, against a threshold you set.

What happens when a tax transcript is missing?

Every year used for income needs its transcript before closing. When the IRS answers “no record”, the transcript matcher looks for an e-file acknowledgement or proof of filing, raises a condition for the processor and requests the transcript again.

Does the underwriter stay in control?

Yes. The agents calculate and recommend; the underwriter decides and signs the income. If the underwriter’s figure differs from the worksheet by more than 5%, or a finding is overridden, the underwriting manager reviews it before it counts.

Can we apply our own overlays?

Yes. Lender overlays are applied after the program’s rules, and the Form 91 rule set, declining-income method, liquidity test and threshold, transcript timing, second reviewer and loan officer notice are all settings, versioned and dated.

How long does it take to go live?

The Agentic Solution Engine builds and deploys it from your requirements — your credit policy, overlays and a sample of past self-employed files — and it goes live once every quality gate has passed. We will walk you through it on your own files first.

See it on
your income files.

We’ll run Self-Employed Income Calculation on a sample of your own self-employed files.