You can be profitable on paper and still struggle to pay your own bills. The gap between the two is usually hiding in one number: how long you wait to get paid. That number has a name — Days Sales Outstanding, or DSO.
What is DSO?
Days Sales Outstanding is the average number of days it takes your business to collect payment after a credit sale. A lower DSO means cash comes back to you faster; a higher DSO means more of your money is tied up in unpaid invoices.
How to calculate it
The standard formula is:
DSO = (Accounts Receivable ÷ Total Credit Sales) × Number of Days
Pick a period — a month, a quarter or a year — and use the number of days in it. For example, take your total outstanding receivables at the end of the period, divide by the credit sales in that period, and multiply by the number of days. The result is your average collection time.
Track it over time rather than obsessing over a single reading. The trend tells the story: a DSO that is creeping up is an early warning that collections are slipping.
What counts as a "good" DSO?
There is no universal target — it depends on your industry and the payment terms you offer. The useful benchmark is your own terms. If you invoice on 30 days but your DSO is 55, customers are effectively taking almost double the credit you agreed to. The closer your DSO sits to your stated terms, the healthier your collections.
Why a high DSO hurts
- It ties up working capital — money owed to you cannot pay suppliers, salaries or growth.
- It increases risk — the older a receivable gets, the harder it is to recover.
- It hides problems — strong sales can mask weak collections until cash runs short.
How to reduce your DSO
Bringing DSO down is rarely about one big move — it is a series of small, consistent habits:
- Invoice immediately. Every day between delivery and invoice is a day added to your DSO.
- Make terms crystal clear. State the due date, amount and method on every invoice.
- Check credit before you extend it. Prevention keeps risky accounts out of your ledger.
- Follow up on a fixed cadence. A structured reminder schedule collects faster than ad-hoc chasing.
- Monitor ageing continuously. Sort receivables into 0–30, 31–60, 61–90 and 90+ days, and act the moment an account drifts.
- Act early on overdue accounts. The first days after a missed due date are when recovery is easiest.
If your DSO is climbing and internal follow-up is not moving the needle, a professional receivables partner can help you tighten the whole cycle — from prevention to recovery to ongoing monitoring.