Supplier Delivery Scores: Which Promise Is Your Purchasing App Measuring?

Before using an on-time delivery score to choose a supplier, define the delivery date, quantities and missing orders behind it. A reassuring percentage can describe only part of your purchasing history. The useful feature is a reviewable supplier record with a follow-up action, not a green badge that silently decides who gets the next order.

This guide concerns reviewing past delivery reliability. Comparing current quotations, forecasting stock and deciding a supplier's contractual responsibility are different tasks.

Keep the promise separate from the latest forecast

Ask which date the comparison uses: your requested date, the supplier's confirmed commitment or the latest expected arrival. Those are not necessarily the same. If staff move an expected date after a delay, a report based only on its current value can answer a different question from “Did the supplier meet the original promise?”

For a custom purchasing app, recommendation: retain the agreed baseline and subsequent changes with their reasons. Show the latest forecast for operational planning without silently replacing the history used for supplier review. Decide whether an authorised renegotiation changes the assessment, and keep that decision visible.

Do not infer blame from lateness alone. Your own late instruction, a disputed receipt or an agreed change may need investigation before staff treat the result as supplier failure.

Decide what counts once and what counts by quantity

An order-level score asks whether an entire order met a rule. A quantity-based score asks how much arrived on time. A supplier sending a small part promptly and most goods later can look different under those measures.

The official Odoo 19 purchase-stock source provides a concrete example. Its on-time-rate computation uses qualifying purchase lines, totals ordered quantities and compares completed stock-movement dates with the lines' planned dates. It compares the date parts, not an exact appointment-style arrival minute.

That is a description of the fetched implementation, not a universal procurement standard or a guarantee for another version, installed extension or customised database. Your developer should demonstrate the actual system and its units before you use its percentage commercially.

Ask which late work is missing from the score

In that Odoo source, the purchase-line selection requires a nonzero received quantity. A line with no receipt therefore does not enter that calculation. The reporting window is based on the order date, and the implementation excludes service products. It uses a negative value to indicate no data rather than assigning a successful score.

For your requirements, ask for a visible separate list of overdue goods with nothing received. Otherwise a delivery score and the buyer's urgent problems may diverge. Show the reporting period, qualifying population and no-data state beside the result. “No qualifying history” should not be rendered as perfect performance.

Also define how returns, corrected receipts, changed quantities and cancelled balances affect your chosen measure. This article does not establish their full treatment from one method or prescribe an accounting policy.

Make the result lead to a review, not automatic punishment

Let a buyer open the relevant orders and receipt evidence from a supplier review. Separate a calculation correction from a commercial decision to contact the supplier, request an explanation or change a future sourcing choice. Require an accountable person and a recorded outcome for disputed cases.

Keep delivery reliability distinct from quality, price and suitability. An on-time score cannot prove that a supplier's products met the specification or that replacing the supplier is the right decision.

Test a deliberately uncomfortable history

Use fictional orders in the acceptance criteria: an on-time receipt, a late receipt, a partly received line and an overdue line with no receipt. Add a revised expected date and a supplier with no qualifying history. State the expected inclusion and business interpretation before running the report.

Require staff to trace each result to its contributing records and to find the overdue excluded work separately. Have the developer calculate the expected result from those exact records rather than demonstrating only a supplier with an uncomplicated history.

Bring this evidence policy to a purchasing-app discussion. The objective is a defensible follow-up process, not an unexplained supplier ranking.

Source boundary

The official Odoo 19 source was fetched and read on 26 October 2026. The cited method supports the implementation examples above; no Odoo instance or supplier dataset was exercised. Baseline preservation, dispute review and acceptance cases are proposed requirements. They do not certify supplier fault or legal compliance.