Cash Flow Underwriting Example, Step by Step

Cash flow underwriting means approving or declining a loan on what the borrower's bank account actually did, not on what the tax return says the business earned. The lender rebuilds true operating revenue from deposits, strips out transfers and loan proceeds, subtracts operating outflows, identifies every existing debt payment leaving the account, and divides the result by total debt service including the new loan. Most US commercial lenders want that ratio at 1.25x or better.

Below is a full worked example, start to finish, on a hypothetical borrower. The company, the numbers and the file are illustrative and built to show the mechanics of the calculation, not a real credit. Every step is the one an analyst actually performs.

The example file

A regional equipment dealer applies for a $250,000 term loan, five years, to buy a service truck fleet. Here is what arrives in the file.

The tax return says the business made $118,000 last year. That figure is the starting point of a credit analysis and the end point of nothing. Here is what the statements said.

Step 1. Rebuild true operating revenue from the deposits

Total deposits across the twelve months came to $3,410,000. That number is not revenue and treating it as revenue is the most common error in this whole exercise. Deposits include anything that hit the account: customer payments, owner injections, transfers from a second account, a tax refund, an insurance settlement, and the proceeds of any borrowing the company took on during the year.

Categorizing the deposit stream produced this split.

True revenue of $2,867,000 against $2,940,000 on the tax return is a 2.5 percent variance, which is normal and reassuring. Accrual timing, year end cutoffs and a handful of customer payments landing in a different month explain gaps of that size. A twenty percent gap would not be normal, and the direction matters: statements well below the return usually means unrecorded discounts or a second account you have not been shown, while statements well above it usually means deposits that are not sales.

Step 2. Strip the non operating outflows

Total withdrawals were $3,289,000. The same discipline applies in reverse. Transfers back to savings, owner distributions and the principal portion of debt payments are not operating expenses, and each has to be handled differently.

• Transfers out ($264,000): removed entirely, they are the mirror of the transfers in.
• Owner distributions ($196,000): removed from operating outflow, then treated as an addback that is available for debt service only if the owner can genuinely live without it. Most analysts haircut this. Here we credited half.
• Debt service ($214,000 total): pulled out of operating expense entirely, because it becomes the denominator of the coverage ratio.
• Everything else ($2,615,000): inventory purchases, payroll, rent, fuel, insurance, card processing fees. This is genuine operating outflow.

Step 3. Find the debt the borrower did not put on the schedule

This is the step that changes decisions. The borrower listed two obligations totaling $3,100 a month. The statements showed six recurring debt-shaped outflows.

The borrower disclosed $3,100 a month. The account was paying $17,817. Two of those are merchant cash advances taken during the year, which is also where the $142,000 of loan proceeds in the deposit stream came from. Nothing here requires assuming the borrower lied. Owners routinely think of a daily MCA debit as a cost of doing business rather than debt, and lease payments are often filed mentally under equipment rather than borrowing. The statements do not care what it is called.

Step 4. Compute net operating cash flow

The distribution addback is a judgment call, not a formula, and it is where two competent analysts will disagree. Adding back the full $196,000 assumes the owner will take nothing if the business needs it. Adding back nothing assumes the owner's pay is untouchable. Half is a defensible middle position, and whatever you choose, write down why. If the owner has a spouse with income covering the household, take more. If the distribution is the household's only income, take none.

Step 5. Compute DSCR with the new loan included

Existing annual debt service is $17,817 a month, or $213,804 a year, which matches the $214,000 pulled out in step two. The requested loan adds roughly $5,000 a month, so $60,000 a year.

Same borrower, same twelve months, same requested loan. The difference between a comfortable 3.60x and a marginal 1.28x is entirely the debt the schedule left out. At 1.28x this file is right at the line most commercial lenders draw at 1.25x, and it is a very different conversation than the one the application invited.

Step 6. Read the behavior, not just the ratio

The ratio is one number. The account tells you how the business lives month to month, and this is where cash flow underwriting earns its keep over a spreadsheet built from a tax return.

A 1.28x DSCR on a stable account is a workable credit with the right structure. A 1.28x DSCR on an account that took a second merchant advance in month nine, ran eleven negative days after that, and posted five of its seven NSF items in the last quarter, is a business whose cash position is tightening while it borrows to stay ahead. The credit decision is not driven by the ratio here. It is driven by the direction.

What an analyst would actually do with this file

Decline is not the only answer, and it is often the lazy one. The realistic paths are to restructure the request so part of the proceeds retires the two merchant advances, which would replace $12,577 a month of daily and weekly debits with a single amortizing payment and materially improve both coverage and the account behavior. Or to reduce and secure the request against the equipment. Or to ask for a personal guarantee supported by a global cash flow analysis that includes the owner's outside income. What you would not do is approve it against the 3.60x the application implied.

Frequently asked questions

What is cash flow underwriting?

Cash flow underwriting is a credit method that bases the decision on money that actually moved through the borrower's bank account rather than on reported earnings. The lender rebuilds true operating revenue from deposits, subtracts operating outflows, identifies all existing debt service, and computes coverage. It is standard practice in small business, merchant advance, revenue based and equipment lending, where tax returns are stale or heavily managed.

How do you calculate cash flow for underwriting?

Start with total deposits, then remove transfers, owner contributions, loan proceeds, refunds and other non revenue credits to get true operating revenue. Subtract genuine operating outflows, excluding debt service and owner distributions. Add back the discretionary portion of distributions you judge available. The result is cash flow available for debt service, which becomes the numerator of DSCR.

What DSCR do lenders require?

Most US commercial banks and equipment finance companies set a 1.25x minimum and prefer comfortably above it. SBA 7(a) underwriting works to a 1.15x minimum on the business under current SOP guidance. Merchant advance and revenue based providers do not use DSCR at all, pricing instead against deposit volume and consistency. Below 1.00x the business cannot service its debt from operations.

How many months of bank statements do lenders need?

Twelve months is the standard for term lending because it captures a full seasonal cycle and lets you see trend rather than a snapshot. Merchant advance and short term working capital providers commonly work from three to six months. Fewer than six months hides seasonality entirely, and a business that looks strong on its three best months can look very different across a year.

Why does cash flow from bank statements differ from the tax return?

Tax returns are accrual based, prepared to minimize tax, and typically nine to eighteen months stale by the time a lender reads them. Bank statements are cash based and current. Small differences come from timing and cutoffs. Large differences usually mean an undisclosed account, revenue recorded that never collected, or deposits that are not sales. The gap itself is a diagnostic, which is why analysts compute both and reconcile them.

What is a good average daily balance for a business loan?

There is no universal figure, so lenders read it as days of coverage: average daily balance divided by average daily operating outflow. Two to four weeks of coverage is typical for a healthy small business. Under one week signals a company operating on the float, where a single delayed customer payment causes an overdraft, regardless of what the annual coverage ratio says.

Doing this at volume

Everything above is roughly four hours of work per file done by hand, and the categorization step is where errors enter. A missed daily MCA debit is easy to overlook in a statement with 400 lines a month, and it moved this file by more than two turns of coverage. It also assumes the borrower's own numbers are worth reconciling against, which is not always true: when a company's books and its bank feed have never been properly reconciled against each other, the interim P&L in the file is closer to an estimate than a record, and the statements become the only reliable source.

Our cash flow underwriting software performs steps one through six from uploaded PDFs, returning categorized deposits, true revenue, the recurring debt payment list, NSF and negative day counts and DSCR, with every figure traceable to the transaction it came from. For files where collateral rather than cash flow carries the credit, our borrowing base software handles the AR aging and ineligibles side, and global cash flow analysis covers the cases where the owner's personal returns have to be combined with the business.