DSO Calculator
Days Sales Outstanding measures how long it takes you to collect on credit sales. The number is useful, but the more interesting question is what it's costing you. This calculator shows both — your DSO against industry benchmarks, and the annual carrying cost of receivables in dollars.
Not sure where to find these numbers in your books? See where to find them in QuickBooks, Wave, or your accountant's report.
Choose an industry to see how your numbers compare to typical businesses like yours.
Trailing 12 months from the income statement.
Period-end AR. Use the average of beginning and ending balances if you want a smoother figure.
Fill in industry, annual revenue, and accounts receivable to see your DSO and what it's costing in carrying cost.
The formula
DSO = (Accounts Receivable / Revenue) × 365A DSO of 45 means your customers take, on average, 45 days to pay after you invoice. Some sources use 360 days instead of 365 (banking convention). Both are valid; we use 365 because it matches calendar reality.
Why DSO matters more than most owners realize
Every dollar tied up in receivables is a dollar you're financing. If your line of credit charges 10% per year, every $100,000 in AR costs you $10,000 a year just in carrying cost. If you don't use a line of credit, the cost is the opportunity cost of what that capital could be doing instead.
The math is brutal at scale. A $2M business with 60-day DSO carries $329,000 in AR. At 10% cost of capital, that's $32,900 per year — flowing out the door, every year, just to finance the gap between "we delivered" and "we got paid."
Industry benchmarks
DSO expectations vary enormously by industry:
- Retail and restaurants: near zero — most sales are cash or card with same-day settlement
- E-commerce: typically 0-15 days — payment processors hold funds briefly
- Professional services: 30-45 days typical, with net-30 terms
- Construction and trades: 45-75 days is common, especially for project work with progress billing
- Manufacturing: 30-60 days for B2B; longer for project-based
Why is your DSO higher than benchmark?
The pattern is almost always one of these four:
- Terms have drifted. Your stated terms are net-30, but in practice you accept 45 or 60 because nobody's following up. Most DSO problems start here.
- A few large customers are dragging the average. Pull AR aging — DSO problems are usually concentrated in 2-3 customers who pay slowly. The rest are fine.
- Invoicing is slow. Invoices that go out late get paid late. If you invoice at month-end for work completed mid-month, you've added 15 days to your effective DSO before terms even start.
- Disputed invoices are sitting unresolved. A customer flagged a discrepancy, nobody followed up, invoice is still in AR three months later. Common pattern, especially in growing businesses.
What to do about high DSO
Quick wins (this week)
- Pull AR aging report. Anything over 90 days needs an immediate phone call (not email)
- Check your three largest customers — concentrated problems get concentrated fixes
- Resolve any disputed invoices currently in AR — they don't age out by themselves
Process changes (this month)
- Invoice on completion, not at month-end. Saves 5-15 days of DSO immediately
- Send a reminder 5 days before due date — most overdue payments are oversights, not refusals
- Establish a follow-up cadence: day 5, day 15, day 30, escalate at day 45
- Consider 2/10 net 30 (2% discount for payment in 10 days) — often pays for itself
Structural changes (this quarter)
- Move to deposit-on-order or progress billing for project work
- Set credit limits on slow-paying customers — no work on new orders until prior balance clears
- Consider invoice financing or factoring for the worst offenders while you fix upstream
- For chronic late payers, evaluate whether the relationship is worth the working capital cost
DSO and the broader cash cycle
DSO is one of three pieces of the cash conversion cycle:
Cash Conversion Cycle = DSO + DIO − DPODSO (Days Sales Outstanding) — how long customers take to pay you.
DIO (Days Inventory Outstanding) — how long inventory sits before becoming revenue.
DPO (Days Payable Outstanding) — how long you take to pay suppliers.
Reducing DSO is one of three levers. Increasing DPO (paying suppliers later, within reason) and reducing DIO (faster inventory turnover) work just as well. The Cash Conversion Cycle calculator combines all three.
FAQ
Should I use period-end AR or average AR?
Either works. Period-end is simpler and more common; average (beginning + ending / 2) is smoother across seasonal cycles. For benchmarking against industry data, check what your data source uses — RMA studies typically use period-end.
What about DSO for cash businesses?
Most retail, restaurants, and direct-to-consumer e-commerce have DSO near zero because customers pay at point of sale. The metric is most useful for B2B businesses with credit terms. If your business is mostly cash, focus on DIO and DPO instead.
Is high DSO always bad?
Not always. Some industries (construction, manufacturing with project work) have inherently long cycles, and competing on shorter terms might cost you customers. The right comparison is to your industry, not zero. The benchmark ranges in this tool are calibrated by industry for that reason.
When is invoice factoring worth it?
Factoring (selling AR for immediate cash at a discount) is expensive — typical fees are 1-3% per month, which annualizes to 12-36%. It's usually a stopgap, not a long-term solution. Worth considering if (a) you have a working capital crunch, (b) the underlying receivables are good quality, and (c) you're actively fixing the upstream process. For chronic high DSO, the better answer is fixing collections rather than financing them.