cash-flow
Days Sales Outstanding (DSO) Calculator
Days Sales Outstanding (DSO) measures the average time between sending an invoice and collecting payment. High DSO ties up working capital — every day extra is a day your money is funding the customer's operations instead of yours. This calculator runs your DSO + flags health tier so you know where to focus AR cleanup.
Educational estimate based on the inputs you entered — not financial, legal, or tax advice. Verify against your specific situation before acting on this output.
How it works
Methodology
Inputs
- Accounts receivable balance
- Total outstanding AR on the balance sheet at the measurement date.
- Annual revenue
- Trailing 12-month revenue. For seasonal businesses, use a rolling 12-month total rather than a single quarter.
Formula
DSO = (Accounts receivable ÷ Annual revenue) × 365 Health bands: • Under 30 days → excellent • 30 – 45 days → healthy (typical B2B target) • 45 – 60 days → watch • 60 – 90 days → high — collection process needs work • Over 90 days → crisis — AR is functionally a free loan to customers
Assumptions
- DSO is industry-dependent — construction businesses with AIA progress billing routinely run 60-90 days as standard, not as crisis.
- Track your own DSO over time — the trend matters more than any absolute benchmark.
- Doesn't model bad debt write-offs separately — AR balances should net out provisions for uncollectible accounts.
- Financing-alternative context: when DSO is high and cleanup takes time, invoice factoring converts the receivable itself into cash rather than waiting out the collection cycle. As of 2026, 10 states require standardized cost disclosure on commercial financing, and several of those laws explicitly cover sales-based financing — the legal category factoring falls into — so a factoring quote should come with the same disclosure rigor as a loan quote.
- The bank-loan alternative isn't fast either: the SBA guaranteed 77,600 loans worth $37 billion through its 7(a) program in fiscal year 2025, but the standard 45-90 day close means a term loan doesn't fix a near-term cash gap caused by slow-paying customers the way factoring against the receivable directly can.
Worked examples
B2B service business
- Accounts receivable
- $95,000
- Annual revenue
- $840,000
DSO 41 days — healthy band for B2B service. Trend matters more than the absolute number.
Frequently asked
Questions readers ask
What's a good DSO for a small business? +
Industry-dependent. B2B service businesses target 30-45 days. Construction (AIA progress billing) commonly runs 60-90. Auto-debit / subscription models can be under 10. Track your own DSO over time — the trend matters more than any absolute benchmark.
How can I reduce my DSO? +
Faster invoicing (send within 24 hours of work completion, not weekly batched), shorter payment terms (net-15 instead of net-30 where possible), upfront deposits, payment incentives (1% discount for net-10), auto-debit for recurring customers, factor your worst-paying accounts.
Is DSO the same as average collection period? +
Yes — DSO and average collection period are the same metric, just different names for it. Both measure the average number of days between invoicing and collecting payment, calculated as (accounts receivable ÷ annual credit sales) × 365. Some analysts distinguish by using only credit sales (excluding cash sales) in the denominator for a more precise number.
How does DSO relate to cash flow? +
DSO directly drives how much of your revenue is sitting uncollected at any given time. A business doing $1M/year at 60 DSO has roughly $164K permanently tied up in receivables versus $82K at 30 DSO — that gap is cash that could otherwise fund payroll, inventory, or debt service. Reducing DSO by even 10-15 days often frees up more working capital than raising a small loan.
My DSO is still in the healthy range — why should I care if it's trending up? +
A rising trend usually signals a real underlying issue — a key customer paying slower, weaker collections follow-up, or looser credit terms extended to win business — well before the number crosses into a 'bad' band. Catching the trend early (quarter-over-quarter, not just year-over-year) lets you fix the process before it becomes a cash crunch.
This tool is for educational purposes only and is not financial, legal, or tax advice. Final terms and eligibility depend on lender underwriting; consult a tax professional before acting on tax-tool output. ClearValue Lending is a funding platform.