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Debtor Days Ratio

Step-by-Step Guide to Understanding Debtor Days Ratio

Last Updated May 2, 2024

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Debtor Days Ratio

How to Calculate Debtor Days

The debtor days ratio, often called days of sales outstanding (DSO), pertains to credit sales, which refers to when customers make a promise to pay for a purchase in cash on a future date.

Companies that sell products or services to customers can be paid in either cash or on credit. For a credit purchase, the company has provided the product or service to the customer, but no cash payment has been received to date.

Until the customer fulfills the payment obligation in cash, the amount owed will be recorded as accounts receivable on the balance sheet.

The accounts receivable of a company is recognized as an asset on the balance sheet, and captures the outstanding credit purchases that have not yet been met.

On the balance sheet, the accounts receivable is recorded in the current assets section because the collection of the cash is expected to be in the near term (within 12 months).

Companies with low debtor days are viewed as more operationally efficient, while companies with high debtor days are perceived as inefficient and might need to implement changes to their business models.

  • Low Debtor Days → Quick Collection of Cash Payment from Credit Purchases
  • High Debtor Days → Slow, Inefficient Collection of Cash Payment from Credit Purchases

Calculating debtor days involves dividing a company’s receivables amount and dividing it by its credit sales for the corresponding period, followed by multiplying the resulting figure by 365 days.

Debtor Days Formula

The formula for calculating the debtor days metric is as follows.

Debtor Days = (Average Accounts Receivables ÷ Credit Sales) × 365 Days

Using a company’s credit sales results in a more accurate metric than using the total sales amount, however, the credit sales data may not always be readily available (in which case using total sales would be the only option).

The rationale for using the average accounts receivable, i.e. the average between the beginning and ending period balances, is to better “match” the accounts receivable period to the sales period. In particular, sales data comes from the income statement, which tracks performance across two periods.

In contrast, A/R is from the balance sheet, which is a snapshot of the assets, liabilities, and equity at a specific point in time.

To match the timing covered in the numerator and denominator, we use the average, but using the ending balance is also acceptable in most cases.

Debtor Days Calculator

We’ll now move to a modeling exercise, which you can access by filling out the form below.


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Debtor Days Calculation Example

Suppose we’re calculating the debtor days for a company with the following financial data.

Credit Sales

  • 2020 = $60 million
  • 2021 = $85 million

Accounts Receivable (A/R)

  • 2020 = $10 million
  • 2021 = $14 million

The average A/R balance is $12 million.

  • Average A/R = ($10 million + $14 million) ÷ 2 = $12 million

By dividing our average A/R by credit sales in 2021 and then multiplying by 365, we arrive at an implied debtor days of 52 days.

On average, our company requires 52 days to collect cash from customers that had paid using credit.

Debtor Days Calculator

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