A source and application analysis compares every dollar a taxpayer spent against every dollar they can show came from a known source. BankXLSX converts years of bank, brokerage, and loan statement PDFs into Excel or CSV with date, description, amount, and running balance in their own columns, so both sides of the schedule trace to a printed line. Start free, no credit card.
Last updated July 2026
Upload your bank statement
Drop file here or click to upload
PDF, JPG, PNG, BMP, HEIC, TIFF, MT940
Uploading...
The source and application of funds method is an indirect way of proving income. It totals every application of funds during a year, meaning money spent, assets bought, and debts paid down, then totals every source of funds, meaning reported income, assets sold, loans taken, and documented nontaxable receipts. When applications exceed sources, the excess had to be funded by income that was not reported. The IRS describes it in IRM 4.10.4.5.3, and courts have upheld it under IRC 446. It is the mirror image of a cash-flow statement, and every line traces to a bank, brokerage, or loan statement, which is why the underlying work is a statement extraction.
The arithmetic is one subtraction. Assembling a complete list of what was spent and a defensible list of where the money came from is where the days go.
The uses side is built from real outflows: card payments, checks, cash withdrawals, asset purchases, and loan principal. Reconstructing it means reading every debit across every account, not estimating.
Every dollar on the sources side needs a document: a paycheck deposit, a loan draw, an asset sale, a gift. Anything you cannot tie to a statement line is treated as unreported income.
Money moved between a taxpayer own accounts is neither a source nor an application, but it appears as a debit in one account and a credit in another. Missing the match double counts the flow.
The method depends on completeness. One account with a gap leaves either an application or a source understated, and the difference between the two sides becomes unreliable.
An asset bought is an application; the same asset sold is a source. A new loan is a source; principal repaid is an application. Balance changes at each end of the year have to be read off the statements.
The schedule only works if every account is captured the same way for the same period. Retyping figures from a dozen statements rarely stays consistent enough to foot.
Upload the statements and get the structured rows a source and application analysis is built on.
Withdrawals, card payments, checks, and cash come out as dated rows, so the applications total is built from actual spending rather than an estimate.
Deposits, loan draws, and asset-sale proceeds land as dated rows, so each source is a statement line you can point to.
Bank, brokerage, and loan statements land with identical columns, so applications and sources stack into one sheet for the whole period.
Older paper statements are usually image-only. OCR tuned for statement layouts reads them instead of returning blank rows.
Because dates, amounts, and descriptions stay intact, a debit in one account matches its credit in another so internal transfers can be netted out.
256-bit encryption in transit, deletion on your schedule, and no reselling or sharing of uploaded financial data.
Nothing to install and no credit card to start.
Upload bank, brokerage, and loan statements for each account across the whole year or years under review so no outflow or receipt is missed.
Tip: Capture loan statements too. Principal paid is an application and a new draw is a source, and both change the answer.
Sum every dollar spent, invested, or used to pay down debt on the uses side, then sum reported income, asset sales, loan proceeds, and documented nontaxable receipts on the sources side.
Tip: Net out transfers between the taxpayer own accounts before totaling either side, or the flow is counted twice.
Subtract total sources from total applications. A positive difference is spending the known sources do not explain, which the method treats as unreported income unless a nontaxable source accounts for it.
Tip: Document the source of every nontaxable adjustment while the statement row is still in front of you.
Anyone who has to test whether spending outran the income a taxpayer can prove.
Rebuild the government schedule to find the source the agent left off, the double-counted transfer, or the nontaxable receipt that closes the gap.
Show that lifestyle and purchases outran documented income in fraud, divorce, and partnership disputes, or prove they did not.
Test a special agent expenditures case line by line, since an unproven application or an ignored source can undo the whole computation.
Check the examiner figures before conceding, or reconstruct income for a client whose records are incomplete.
The method sets everything a taxpayer did with money against everything they can show funded it. If the uses are larger than the proven sources, the difference is treated as income that was left off the return.
| Side | Item | Where it comes from |
|---|---|---|
| Applications | Personal living expenses | Card, check, and cash outflows for the year. |
| Applications | Increases in assets | Property, vehicles, and investments bought. |
| Applications | Decreases in liabilities | Loan and card principal paid down. |
| Sources | Reported income | Wages and business receipts already declared. |
| Sources | Decreases in assets | Proceeds from assets sold during the year. |
| Sources | Increases in liabilities and nontaxable receipts | New loans, gifts, inheritances, and loan draws. |
| Result | Applications minus sources | A positive figure is unexplained, so it is treated as unreported income. |
IRM 4.10.4.5.3 sets out the examiner version, and the courts have accepted it under IRC 446 in both civil and criminal cases. The theory is that money cannot be spent twice: whatever left the accounts had to come from somewhere, and any use the known sources do not cover points to income that was not declared.
Examiners choose among four related tools depending on how the records fail. They often run more than one and reconcile the results.
| Method | What it measures | Best fit |
|---|---|---|
| Source and application | Uses of funds against proven sources | Spending outran documented income |
| Net worth | Change in assets minus liabilities | Wealth grew faster than income |
| Bank deposits | Money flowing through accounts | Most receipts passed through a bank |
| Cash-T and markup | Cash in against cash out, or cost grossed up | Cash business holding back receipts |
The source and application method is close kin to the net worth method. Net worth looks at balances at two dates; source and application looks at the flows in between. They should reconcile, and an examiner who builds one often checks it against the other.
The defense is almost always in the completeness of the sources side, not the arithmetic.
Once the outflows and receipts are rows, the rest is ordinary spreadsheet work. Many engagements run this alongside the balance side, the net worth method, and reconcile the two. The deposit total often comes straight from a bank deposit analysis, and cash businesses pair it with a cash intensive business audit workup. If the matter is IRS collection or examination, the same data feeds the bank statement converter for tax resolution and Form 433. Start from the source documents with the bank statement converter, use running balance extraction for period tie-outs, and speed the build with transaction categorization.
Firms that run these engagements repeatedly automate the intake rather than the analysis. Once the two sides reconcile you can turn the figures into presentation-ready financial statements without rekeying, and teams handling the rest of a client document set at volume extract it with enterprise document OCR.
It is an indirect method of proving income that totals every use of funds during a period, such as spending, asset purchases, and debt repayment, then totals every proven source, such as reported income, loans, and asset sales. When applications exceed sources, the unexplained excess is treated as income that was not reported.
The net worth method compares assets minus liabilities at two dates and measures the change. The source and application method looks at the flows in between, setting money spent against money proven to have come in. They measure the same thing from two angles and should reconcile, which is why examiners often build both.
Reported wages and business income, proceeds from selling an asset, new loan and line of credit draws, and documented nontaxable receipts such as gifts and inheritances all count as sources. Cash the taxpayer can prove they held before the period also counts. Anything you cannot tie to a document is not treated as a source.
A transfer between a taxpayer own accounts is neither a source nor an application. It shows up as a debit in one account and a credit in another, so if it is not matched and removed it inflates both sides of the schedule and distorts the difference. Netting transfers out is one of the first steps.
You need every bank, brokerage, credit card, and loan statement for the whole period, for every account the taxpayer controlled. The method depends on completeness, so a single missing month can understate an application or a source and make the comparison unreliable.
No. It converts statement PDFs into accurate Excel or CSV rows with dates, descriptions, amounts, and running balances so the applications and sources can be totaled and defended. Classifying each flow and reaching conclusions remains the work of the CPA, EA, or attorney.
Yes. The expenditures and source and application approach is one of the accepted methods of proof in criminal tax investigations, and convictions have been upheld on it. That is why proving every legitimate source and avoiding double-counted transfers is so central to the defense.
At least every year under examination, with every account captured for each year. Because the method sums flows rather than balances at a single date, you need continuous statement coverage across the period, plus documentation of any cash or assets held going into it.
The balance-based sibling method.
The deposit side of the same problem.
Where all four methods run together.
Income averaging for IRS Form 433.
Trace hidden and diverted funds.
From the same family of tools
Get started converting bank statements to spreadsheets.
USD
per month
billed as
$288 yearly
Choose speed vs accuracy when extracting
| Base AI Faster | 2,500 pages |
| Pro AI Best accuracy | 500 pages |
Scale statement conversion across your team with automation.
USD
per month
billed as
$888 yearly
Choose speed vs accuracy when extracting
| Base AI Faster | 10,000 pages |
| Pro AI Best accuracy | 2,000 pages |
Enterprise-grade bank statement conversion and controls.
USD
per month
billed as
$ yearly
Choose speed vs accuracy when extracting
| Base AI Faster | pages |
| Pro AI Best accuracy | pages |
