Cash Flow & AR
Days Sales Outstanding (DSO) Explained for Small Business
Short answer
Days Sales Outstanding (DSO) is the average number of days between invoicing and getting paid. Calculate it as (accounts receivable ÷ total credit sales) × days in period. A healthy DSO for small service businesses is 30–40 days; under 25 is excellent.
DSO is the single best one-number measure of how quickly your invoices turn into cash. Tracking it monthly turns 'we feel like collections is getting worse' into a concrete trend you can act on. It is also the metric most affected by every other tactic in this hub — every Faster Payment improvement shows up as a lower DSO.
How to calculate DSO
DSO = (Accounts Receivable ÷ Total Credit Sales) × Number of Days in the Period.
Example: in June (30 days), your business had $60,000 in invoiced sales and ended the month with $40,000 in outstanding AR. DSO = ($40,000 ÷ $60,000) × 30 = 20 days.
Track DSO monthly using a rolling 90-day window — a single month can be volatile, especially for seasonal businesses.
What is a good DSO?
DSO benchmarks vary by industry, but for small service businesses:
| DSO range | Interpretation |
|---|---|
| Under 25 days | Excellent — fast collections, healthy cash flow |
| 25–40 days | Healthy — typical for well-run small businesses |
| 40–60 days | Watch list — investigate aging and Net terms |
| 60+ days | Problem — collection process is failing or terms too long |
How to lower DSO
Every tactic in the Faster Payment cluster directly reduces DSO. The largest single move is usually shortening default terms (Net 30 → Net 15), followed by adding online payment links and automating reminders. Tracking DSO month over month tells you which changes are actually working.
Frequently asked questions
Is a lower DSO always better?
Almost always — but a DSO of zero is unrealistic and usually means you only take cash up front, which can cost you sales. The goal is the lowest DSO that does not lose you customers.
Does DSO include cash sales?
No — DSO is calculated on credit sales (invoiced sales) only. Cash sales are already collected and do not affect DSO.
Put this guide to work.
Glo Invoice automates reminders, takes online payments, and tracks your AR — free for 14 days.
Sources & further reading
Primary sources we consulted when writing and reviewing this guide.