---
id: KB-IC-013
url: https://app.codecontract.io/help/reports-and-quality/the-trial-period-for-a-new-supplier
idioma: en
categoria: informes-y-calidad
subcategoria: calidad
audiencia: usuario
nivel: intermedio
actualizado: 2026-08-13
tambienEn: [es]
relacionados: [KB-IC-005, KB-CR-014]
citadoPor: [KB-IC-004]
---

# The trial period for a new supplier

_Six months to find out whether they work, with criteria decided before starting._

**Responde a:** approving a new supplier · supplier trial period · criteria to evaluate a supplier · when to stop working with a supplier

A new supplier almost always comes in on price or urgency, and their evaluation is left to the general impression of whoever deals with them most. Six months later nobody can say whether they work better or worse than the previous one, because nobody decided in advance what would be looked at.

## The four criteria that suffice

| Criterion | How it is measured | When to worry |
| --- | --- | --- |
| Meets deadlines | On-time deliveries over the total | If it worsens after the first deliveries |
| Meets specification | Quality incidents per delivery | Any repeat of the same defect |
| Responds on documents | Days to supply what is requested | More than a week on average |
| And warns when something is wrong | How many problems they told you before you saw them | If the answer is zero |

> [!IMPORTANT]
> The fourth is not measured in numbers and best predicts how the relationship will go. A supplier who warns of a delay three days ahead is worth more than one who hits 98% and tells you about the 2% when the lorry does not arrive.

## How to run the period

1. **Write the criteria before the first delivery** — Four, with thresholds. Written afterwards, they get written to justify the conclusion you already had.
2. **Record incidents as they happen** — In their file, not in the memory of whoever suffered them.
3. **Review at three months, not only at the end** — That is when it can still be corrected; at the end you only decide.
4. **And close with a written decision** — Approved, approved with conditions, or not. All three are valid answers.

> [!WARNING]
> The awkward case is the supplier who performs but is hard to work with. If that is not among the criteria, the decision will still be taken on that basis, only without being explainable — and that conversation with the supplier cannot then be had.

## What makes the period useful

**En corto**

- That the supplier knows they are on trial and against what criteria.
- That incidents are raised as they happen, not at the end.
- And that the decision comes on the planned date, not when someone remembers.

The first changes the outcome most: a supplier who knows they are being evaluated, and how, behaves differently — and that is information about them too.

> [!NOTE]
> The same scheme suits an external collaborator, a subcontractor or an advisory firm. What is measured in criterion two changes; the other three are identical.

**Always six months?**

Long enough for ten or twelve deliveries. Two tell you nothing.

**What if they fail on the first delivery?**

Record it and raise it; one bad delivery does not decide, repeating it does.

**Is formal approval required?**

It depends on your quality scheme; a written decision is worth having anyway.

## Ejemplos

**A company brings in a supplier on price and six months later argues about keeping them.**

- Writes four criteria before the first delivery
- Reviews at three months and raises two incidents

→ The final decision is made on data and the supplier knew from the start what was being measured.

**A new supplier enters a trial period and nobody defines what will be looked at.**

- Sets what will be measured and for how long
- Records every delivery and every incident
- Reviews at the end with the data in front of you

→ The decision to continue is taken on facts rather than an impression.

**The period ends and nobody decides anything.**

- Sets a review date at the start

→ The trial period genuinely ends.

**Continuing is decided by inertia.**

- Checks the record before deciding

→ The decision is taken on a basis.

**The supplier does not know they are on trial.**

- Tells them and shares what will be measured

→ The supplier gets a chance to succeed.

**The supplier is dropped and there is no record of why.**

- Records the reason for closing

→ The decision is explicable months later.