How to Calculate Supplier OTIF (On-Time In-Full)

OTIF — on time, in full — is the share of a supplier's purchase orders that arrived by the promised date and with the full quantity. It is the most widely used single measure of supplier reliability, and it feeds directly into how much safety stock you need.

The OTIF formula

On time  = received date ≤ expected date
In full  = quantity received ≥ quantity ordered
OTIF %   = POs that were both on time and in full ÷ POs received in the period × 100

Pick a window and stick to it

Measure over a trailing window — 90 days is common — keyed on the date each PO was received. A trailing window shows whether a supplier is getting better or worse; an all-time number hides it.

Worked example

Illustrative numbers: a supplier delivered 47 purchase orders in the last 90 days. 38 arrived on time; of those, 34 were also complete.

OTIF = 34 ÷ 47 × 100 = 72.3%

Note what OTIF does not tell you: how late the late ones were. A supplier that misses by one day and one that misses by three weeks can have the same OTIF. Track average days late alongside it.

Mistakes that make OTIF misleading

• Reporting 0% for a supplier with no deliveries in the window. That is "no data", not bad performance — show it as unknown.
• Moving the expected date when the supplier says they'll be late. Then everything is on time. Keep the original promised date.
• Averaging OTIF across suppliers equally. A supplier you spend $500 with shouldn't weigh as much as one you spend $500,000 with; weight the overall figure by spend.
• Ignoring overdue POs. An order that hasn't arrived and is past due is already late, even though it isn't in the received count yet. Flag it.

What to do with a low OTIF

• Raise safety stock for that supplier's SKUs — the statistical safety stock formula does this automatically through lead-time variability.
• Use the real lead time, not the contract one, in reorder points.
• Bring the numbers to the next supplier review; dated PO history is hard to argue with.

Supply Chain Manager builds a supplier scorecard from your purchase orders: trailing 90-day OTIF per supplier, a spend-weighted overall figure, and alerts for overdue POs. Suppliers with no deliveries in the window show as unknown, never 0%. One limit to know: if your data has no partial-receipt quantity, "in full" can only mean "received". To see it on sample data, open the live demo.