Bad debt expense is the dollar amount of customer invoices and loans a business expects it will never collect. When a company sells goods or services on credit, some customers inevitably fail to pay. Bad debt expense captures that cost on the income statement, reducing reported profits to reflect the reality that not every sale turns into cash. It shows up as an operating expense, and how you record it depends on the size of your business and the accounting method you use.
How Bad Debt Expense Works
Any time a business extends credit, it creates an account receivable, essentially an IOU from the customer. Most customers pay on time. But when one doesn’t, and there’s no reasonable expectation the money is coming, that unpaid balance becomes a bad debt. The expense entry removes the uncollectible amount from accounts receivable and records the loss.
Suppose your company invoices a customer for $5,000 worth of consulting work. Six months pass, the customer goes bankrupt, and you have no way to recover the money. That $5,000 becomes a bad debt expense. It lowers your net income for the period and reduces the accounts receivable balance on your balance sheet, giving a more honest picture of what your business actually earned and what it’s owed.
Two Methods for Recording It
Businesses use one of two approaches to put bad debt expense on the books: the direct write-off method or the allowance method. They differ in timing, accuracy, and which accounting rules they satisfy.
Direct Write-Off Method
This is the simpler approach. You record a bad debt expense only when a specific invoice is clearly uncollectible. No estimates, no reserve accounts. You wait until a customer defaults, then write off that exact amount. Smaller businesses commonly use this method because it’s straightforward and deals in known figures rather than projections.
The downside is timing. If you make a $10,000 sale in January but don’t realize the customer can’t pay until August, the expense lands in a different period than the revenue it relates to. That gap violates the matching principle, a core rule in accrual accounting that says expenses should be recorded in the same period as the revenue they helped generate. For this reason, the direct write-off method doesn’t comply with generally accepted accounting principles (GAAP) for most businesses.
Allowance Method
Under the allowance method, you estimate future bad debts at the time of the sale and set aside a reserve, called an allowance for doubtful accounts. This means the expense hits the income statement in the same period as the revenue, satisfying the matching principle and producing more accurate financial reports.
The trade-off is precision. Because you’re estimating before you know which specific invoices will go unpaid, the number is inherently approximate. The allowance sits as a contra-asset on the balance sheet, reducing the net accounts receivable figure. When a specific invoice is later confirmed uncollectible, you write it off against the allowance rather than recording a new expense. GAAP requires the allowance method for businesses that regularly sell on credit and have enough history to make reasonable estimates.
Three Ways to Estimate the Amount
If you use the allowance method, you need a way to calculate how much to set aside. There are three common estimation techniques, each with its own logic.
Percentage of Sales
Multiply your net credit sales for the period by a percentage based on your historical experience with uncollectible accounts. If you’ve found that roughly 2% of credit sales go unpaid, and you had $500,000 in credit sales this quarter, your bad debt expense would be $10,000. This method ignores any existing balance in the allowance account. It focuses purely on new sales activity, making it simple to apply but less responsive to shifts in the quality of your outstanding receivables.
Percentage of Receivables
Instead of looking at sales, this method starts with the ending balance of accounts receivable and applies an estimated uncollectibility rate. The key difference: you factor in whatever balance already sits in your allowance account. If the target allowance is $15,000 and you already have $6,000 in the reserve, the adjusting entry is only $9,000. This approach recalibrates each period, which can produce a more accurate balance sheet.
Aging of Accounts Receivable
This is the most granular technique. You sort all outstanding invoices into buckets based on how long they’ve been unpaid: current, 1 to 30 days past due, 31 to 60 days, 61 to 90 days, and so on. Each bucket gets a different estimated uncollectibility rate, with older invoices assigned higher percentages because the longer a bill goes unpaid, the less likely collection becomes. An invoice 90 days overdue might carry a 20% uncollectibility rate, while one that’s current might carry only 1%.
You multiply each bucket’s total by its rate, then add the results to get your target allowance balance. Like the percentage-of-receivables method, you adjust for any existing balance in the allowance account before recording the expense. The aging method takes more effort but gives the most detailed view of credit risk in your receivables.
How It Affects Financial Statements
Bad debt expense flows through two financial statements. On the income statement, it appears as an operating expense, directly reducing net income. A company with $1 million in revenue and $30,000 in bad debt expense reports lower profits than it would if every customer paid in full.
On the balance sheet, the allowance for doubtful accounts is subtracted from gross accounts receivable. If your receivables total $200,000 and your allowance is $12,000, the net receivable reported is $188,000. This gives investors and lenders a more realistic sense of how much cash the business can actually expect to collect. A rising bad debt expense over several periods can signal deteriorating customer credit quality or overly aggressive sales practices, both red flags for anyone evaluating the company’s financial health.
Tax Rules for Bad Debt Deductions
The IRS allows businesses to deduct bad debts, but the rules are specific. A debt is deductible only in the year it becomes worthless, meaning there is no reasonable expectation of repayment. You don’t have to wait until the debt’s due date to make that determination, but you do need to show that you took reasonable steps to collect. Filing a lawsuit isn’t required if you can demonstrate that a court judgment would be uncollectible anyway.
For tax purposes, the IRS generally requires the direct write-off method. That means you can only deduct a specific, identifiable bad debt once it’s confirmed worthless, not an estimated allowance. This creates a common split: many businesses use the allowance method for their financial statements (because GAAP requires it) but switch to the direct write-off method on their tax returns.
One important distinction is between business and nonbusiness bad debts. Business bad debts, those arising from your trade or business operations, are fully deductible as ordinary losses. Nonbusiness bad debts, like a personal loan to a friend that goes unpaid, are treated as short-term capital losses with more limited deductibility.
A Practical Example
Say you run a wholesale distribution company. Over the past three years, about 3% of your credit sales have gone uncollected. This year, you had $800,000 in credit sales. Using the percentage-of-sales method, you’d record a bad debt expense of $24,000. On your books, you’d debit bad debt expense for $24,000 and credit the allowance for doubtful accounts for the same amount.
Three months later, a customer who owes $4,500 files for bankruptcy and you confirm the debt is uncollectible. You write off that invoice by debiting the allowance for doubtful accounts by $4,500 and crediting accounts receivable by $4,500. Notice that the write-off doesn’t create a new expense. The expense was already recorded when you set up the allowance. The write-off simply uses the reserve you already built.
If that same customer later pays $2,000 of the $4,500, you reverse part of the write-off and record the cash receipt. These recoveries reduce the net cost of bad debts over time.
Keeping Bad Debt Expense Under Control
Bad debt expense is a normal cost of doing business on credit, but it shouldn’t grow unchecked. Running credit checks before extending terms to new customers, setting clear payment deadlines, and following up on overdue invoices promptly all help keep the number manageable. Reviewing your aging schedule regularly lets you spot problem accounts early, before a $500 overdue invoice quietly becomes a $15,000 write-off. The goal isn’t to eliminate bad debt expense entirely, which would likely mean turning away good customers, but to keep it proportional to your sales and consistent with your historical experience.