How fast are my customers paying me?
Your payment terms say Net 30. But how long are customers actually taking? The gap between your terms and reality is where cash flow problems hide. Here's how to measure it.
The short answer
How fast are customers paying?The metric you need is Days Sales Outstanding (DSO). It measures the average number of days between sending an invoice and receiving payment. Your accounting software has the data, but you need to calculate DSO yourself. Below, we'll show you how.
Why your collection speed directly controls your cash flow
You have Net 30 payment terms. But your average customer is paying in 47 days. That 17-day gap doesn't sound like much, but do the math: if you invoice $80,000/month, that extra 17 days means you're carrying an additional $45,000 in unpaid receivables at any given time.
That's $45,000 sitting in your clients' bank accounts instead of yours. It's money you've earned, expenses you've already paid, and cash you can't use for payroll, growth, or emergencies.
Improving your DSO by even 5 days can free up tens of thousands in working capital. But first, you need to know your actual number.
What days sales outstanding (DSO) measures and how to calculate it
DSO is the average number of days it takes to collect payment after an invoice is issued. The formula is:
For example, if you have $38,000 in accounts receivable and $80,000 in credit sales over the past 30 days:
($38,000 / $80,000) x 30 = 14.25 days DSO
A lower DSO means customers are paying faster. A higher DSO means payments are slowing down. What counts as “good” depends on your industry and payment terms, but in general:
- DSO below your payment terms: excellent. If you offer Net 30 and your DSO is 24 days, your clients are paying ahead of schedule.
- DSO at or slightly above terms: typical. A DSO of 33 days on Net 30 terms is normal. Most clients pay a few days late.
- DSO significantly above terms: a problem. If your DSO is 50+ days on Net 30 terms, you have a systemic collection issue that is eating your cash flow.
How to calculate your collection speed in QuickBooks Online (5 steps)
QuickBooks does not have a built-in DSO report. You need to pull data from two reports and do a simple calculation.
- 1Get your accounts receivable balance
Go to Reports→ search “Balance Sheet.” Run it as of today. Look for “Accounts Receivable” under Current Assets. Write down this number.
- 2Get your total sales for the period
Go to Reports→ search “Profit and Loss.” Run it for the last 30 days (or 90 days for a more stable number). Note the “Total Income” figure.
- 3Calculate DSO
Divide Accounts Receivable by Total Income, then multiply by the number of days in the period. Example: $38,000 AR / $240,000 revenue (90 days) x 90 = 14.25 days. That's your DSO.
- 4Compare to your payment terms
If your terms are Net 30 and your DSO is 14 days, you're in great shape. If your DSO is 48 days, customers are paying an average of 18 days late.
- 5Check the A/R Aging Summary for problem clients
Go to Reports→ “A/R Aging Summary” to see which specific clients are dragging your DSO up. A few chronic late-payers can skew your entire average.
Total time: about 10-15 minutes. Two reports and one calculation. To track the trend, you'll need to do this every month and record the results.
How to calculate your collection speed in Xero (5 steps)
Like QuickBooks, Xero does not have a dedicated DSO metric. You need to pull data from two reports and do the math.
- 1Get your accounts receivable balance
Go to Accounting → Reports → Balance Sheet. Look for “Accounts Receivable” under Current Assets. Note the total.
- 2Get your total revenue for the period
Go to Accounting → Reports → Profit and Loss. Set the date range to the last 90 days. Note the “Total Revenue” figure.
- 3Calculate DSO
(Accounts Receivable / Total Revenue) x 90 days = your DSO. A 90-day period smooths out month-to-month fluctuations and gives you a more reliable average.
- 4Check the Aged Receivables Summary for outliers
Go to Accounting → Reports → Aged Receivables Summary. Look for clients with large balances in the 31-60 and 61-90 day columns. These are the ones pulling your DSO up.
- 5Track DSO monthly
Record your DSO in a simple spreadsheet each month. A rising DSO over 3+ months means your collection is getting slower. A falling DSO means your efforts are working.
Total time: about 10-15 minutes. The calculation is simple, but tracking the trend over time requires discipline and a spreadsheet.
What it takes to monitor collection speed every month
Calculating DSO once is useful. Tracking it monthly is where the real insight comes from:
- The number alone is not enough.DSO of 38 days doesn't tell you much in isolation. Was it 32 last month? Then payments are slowing down. Was it 45? Then your collection efforts are working. Context comes from the trend.
- One client can skew everything. If your largest client pays 20 days late on a $30,000 invoice, it can add 5+ days to your overall DSO. You need to identify these outliers separately.
- Improving DSO is a process, not a report.Measuring DSO tells you there's a problem. Fixing it requires faster invoicing, clearer terms, earlier follow-ups, and sometimes difficult conversations with slow-paying clients.
Or track your collection speed automatically, every month
Bottomline connects to your QuickBooks or Xero account and calculates your DSO automatically each month. It also tracks the trend and flags clients who are consistently slow:
The key insight Bottomline provides: not just your overall DSO, but which specific clients are dragging it up and by how much. If Acme Corp alone adds 6 days to your DSO, you know exactly where to focus your collection efforts for maximum impact.