What is days payable outstanding (DPO)?
Days payable outstanding (DPO) is the average number of days a company takes to pay its suppliers after receiving an invoice. A higher DPO means you hold on to your cash longer before it leaves the bank. It is the mirror image of days sales outstanding: DSO measures how fast customers pay you, DPO measures how fast you pay others.
Your bank balance does not move when you receive a bill, only when you pay it. That gap between the invoice date and the payment date is free, short-term financing from your vendors, and DPO puts a number on it.
For a startup counting months of runway, this matters because runway is a cash measure. Paying the same bills ten days later changes no line of your profit and loss, yet it changes how much money is in the account today.
The DPO formula, step by step
The formula is DPO = (accounts payable ÷ cost of goods sold, or credit purchases) × days in the period. Accounts payable is what you owe suppliers at the end of the period. Use the same period for both numbers, and the same way of counting every time, so that changes reflect behavior and not method.
A worked example, with made-up numbers: over a 90-day quarter a startup buys $180,000 of cloud hosting, contractors and other supplies on credit, and ends the quarter owing $60,000. DPO = ($60,000 ÷ $180,000) × 90 = 30 days. On average, it pays its bills about a month after they arrive.
Software startups often have little classic cost of goods sold. In that case many teams use total vendor spend on credit as the denominator. That is a reasonable shortcut as long as you say which one you used and stay consistent.
30 days
starting DPO ($60,000 owed on $180,000 of quarterly purchases)
$30,000
one-time cash kept when DPO moves from 30 to 45 days
+1.5 months
extra runway at $20,000 net burn, once
How DPO changes your runway
Continue the example. At 45 days, the same quarterly purchases leave $90,000 owed instead of $60,000. That extra $30,000 stays in the bank. With $200,000 of cash and $20,000 of monthly net burn, runway moves from 10 months to 11.5 months.
The key word is once. Stretching payments is a one-time shift in timing, not a lower burn rate. After you reach the new, longer payment habit, you still pay the same bills every month. If you later return to 30 days, the $30,000 leaves again.
That is why a rising DPO is a short-term lever and not a strategy. It buys months to hit a milestone, not a way to become profitable.
DPO, DSO and the cash conversion cycle
The cash conversion cycle combines three timing metrics into one: days inventory outstanding, plus DSO, minus DPO. It tells you how many days your cash is tied up between paying for inputs and collecting from customers. A shorter cycle is better, and a negative one means customers fund your operations.
Software companies usually carry no inventory, so the simplified version is DSO minus DPO. If customers take 40 days to pay and you take 30 days to pay vendors, you finance about 10 days of operations yourself. Moving either number closes the gap.
| DSO (customers pay you) | DPO (you pay suppliers) | |
|---|---|---|
| What it measures | Days to collect after a sale | Days to pay after a bill |
| Better direction | Lower | Higher, within reason |
| Effect on cash | Slow collection ties cash up | Slow payment keeps cash in the bank |
| Main risk | Customers who pay late | Damaged supplier trust |
| Example | 40 days | 30 days |
How high is too high?
There is no universal benchmark, because the right DPO depends on the terms you agreed. A healthy habit is to pay on the due date, not before and not long after. If your terms are net 30 and your DPO is 32, that is normal. If it is 75, you are paying late, and the vendor knows.
Late payment has costs that do not show up in the formula. Suppliers may add late fees, demand prepayment, reduce service levels or stop working with you. Some early-stage founders stretch the payments of a critical vendor to survive a bad quarter and then discover that the vendor will not extend credit again.
Paying early can also be a mistake. If a supplier offers no discount, paying 15 days before the due date gives them your cash for free. Treat the due date as the target, and negotiate terms before you sign.
How to manage DPO without hurting suppliers
Start by negotiating longer terms upfront. Net 45 or net 60 on a large, predictable vendor is worth more than a habit of paying late. Offer something in return, such as a longer commitment or a reliable payment date, so the arrangement is a trade and not a favor.
Next, pay on the due date by scheduling payments, not by remembering them. Batch payments weekly, and keep a short list of vendors who cannot be delayed, such as payroll providers, tax authorities and critical infrastructure.
Finally, track DPO and DSO together every month. If DSO rises faster than DPO, the gap is draining cash even when revenue grows. Our guides to DSO and to cash flow versus profit show the receivables side of the same picture.
Feeling payment timing in Founder Runway
In Founder Runway, a run lasts 20 turns and every decision has four options. You choose a B2B, B2C or B2G business model and start at Pre-Seed, Seed, Pre-Series A or Series A, then manage cash, burn and runway as your choices play out. It is a learning game, not financial advice, but it makes cash timing feel real.
A run can end in failure, a promising outcome, EBITDA positive or high-value exit potential. Replaying with a different model is a quick way to see why when money moves matters as much as how much.
Frequently asked questions
What is days payable outstanding (DPO)?
Days payable outstanding is the average number of days a company takes to pay its suppliers after receiving an invoice. A higher number means cash stays in the bank longer. It is calculated by dividing accounts payable by cost of goods sold or credit purchases and multiplying by the days in the period.
How do you calculate DPO?
DPO = (accounts payable ÷ cost of goods sold or credit purchases) × days in the period. For example, $60,000 owed against $180,000 of purchases over 90 days gives a DPO of 30 days. Use the same period and definition every time.
Is a high DPO good for a startup?
A higher DPO keeps cash in the bank longer, but only within the terms you agreed. Paying well past the due date risks late fees, lost credit and damaged supplier relationships. A DPO close to your stated payment terms is a sound target.
How does DPO affect runway?
Stretching DPO delays cash leaving the account, which raises your balance once. In a fictional example, moving from 30 to 45 days kept $30,000 in the bank and extended runway from 10 to 11.5 months. It does not lower monthly burn.
What is the difference between DPO and DSO?
DSO measures how many days customers take to pay you, while DPO measures how many days you take to pay suppliers. You want DSO low and DPO reasonable. The gap between them, with inventory, forms the cash conversion cycle.
Test this decision in the game.
Apply the same assumption across one run and see which metric weakened three turns later.