In procurement, buyers often ask how important they should be to a supplier. Should your company represent 5%, 20%, or 40% of a supplier’s annual turnover? The answer matters because your share of a supplier’s turnover affects bargaining power, supplier dependency, risk exposure, and the quality of the relationship.
A very small share may mean that the supplier may not prioritize you. A very large share may create dependency and business continuity risk. Somewhere between those extremes, there is often a healthier balance.
In this article, we look at what share of supplier turnover means, why the common 20% guideline is useful, when it should be challenged, and how tactical buyers can use the concept in supplier management and sourcing decisions.
LHTS procurement framework
Role: Tactical procurement
Process: Supplier management, sourcing strategy, category management
Level: Advanced
Related course: Get to know Kraljic and his matrix
Quick answer: what is a healthy share of supplier turnover?
A healthy share of supplier turnover is the percentage of a supplier’s annual revenue that gives the buyer enough influence without creating unhealthy dependency. A common rule of thumb is that a buyer should normally avoid representing more than around 20% of a supplier’s turnover.
However, 20% is not a fixed rule. The right level depends on the category, market alternatives, supplier risk, switching cost, strategic importance, and the maturity of the supplier relationship.
In tactical procurement, share of supplier turnover should be used as a risk and relationship indicator, not as a mechanical decision rule.
What does share of supplier turnover mean?
Share of supplier turnover means how much of a supplier’s annual revenue comes from your company.
The basic calculation is:
Your annual spend with the supplier ÷ supplier’s annual turnover × 100 = your share of supplier turnover
Example:
Your company spends €2 million per year with a supplier.
The supplier’s annual turnover is €10 million.
€2 million ÷ €10 million × 100 = 20%
This means your company represents 20% of the supplier’s annual turnover.
For a tactical buyer, this number is important because it says something about the balance in the relationship. It helps answer questions such as:
- Are we an important customer for this supplier?
- Are we too dependent on this supplier?
- Is the supplier too dependent on us?
- Do we have enough influence to drive improvement?
- Would the supplier be financially exposed if we changed supplier?
- Would we be exposed if the supplier lost capacity, quality, or financial stability?
The percentage alone does not give the full answer, but it starts an important procurement discussion.
Why the 20% guideline exists
The 20% guideline is often used because it represents a balance between influence and dependency.
When a buyer represents around 20% of a supplier’s turnover, the buyer is usually important enough to receive attention, service, and management focus. The supplier has a clear commercial reason to protect the relationship.
At the same time, the supplier is not completely dependent on one customer. Losing the buyer would hurt, but it would not necessarily destroy the supplier’s business.
That balance can be useful. It gives the buyer a meaningful position without creating excessive supplier dependency.
But the guideline should never be used without judgment. A 20% share can be healthy in one category and risky in another. A 10% share can be powerful in a fragmented market. A 30% share can be acceptable in a strategic partnership with strong governance. The number must always be interpreted in context.
Why share of supplier turnover matters in procurement
Share of supplier turnover affects several parts of procurement work. It is not only a financial number. It influences behavior, negotiation, service levels, risk, and long-term supplier development.
1. Supplier dependency
If your company represents a large share of the supplier’s turnover, the supplier may become dependent on your business. That can create advantages, but also risks.
The advantage is that the supplier will probably prioritize you. You may get stronger account management, faster response times, better access to capacity, and greater willingness to adapt.
The risk is that the supplier may become too exposed to your decisions. If your demand drops, if you change supplier, or if your business strategy changes, the supplier may face serious financial pressure. That can affect quality, delivery performance, investment capability, and long-term stability.
A high share of supplier turnover is therefore not automatically positive. It can give influence, but it can also create fragility.
2. Bargaining power
A meaningful share of supplier turnover can improve your bargaining position. If you are an important customer, the supplier has a reason to listen.
This can support negotiations around price, payment terms, delivery performance, quality improvement, sustainability requirements, innovation, and service levels.
But bargaining power should not be confused with domination. If a buyer pushes too hard when the supplier is highly dependent, the relationship can become unhealthy. The supplier may accept terms that are not sustainable. That can later appear as quality problems, delayed deliveries, lack of investment, or reduced innovation.
Strong procurement is not only about getting leverage. It is about using leverage responsibly.
3. Risk management
Share of supplier turnover is an important supplier risk indicator.
If your company represents a very high share of the supplier’s turnover, the supplier’s financial stability may be closely linked to your decisions. If your spend falls, the supplier may struggle.
There is also a reverse risk. If the supplier depends heavily on your business, they may lack a diversified customer base. That can make them less resilient to market changes.
The buyer should therefore ask:
- How financially stable is the supplier?
- How diversified is the supplier’s customer base?
- What happens if our demand changes?
- What happens if the supplier loses another major customer?
- Do we have alternative suppliers?
- Would switching supplier be difficult, costly, or slow?
This is why share of supplier turnover should be part of supplier risk assessment, especially for critical and strategic suppliers.
4. Supplier development
A higher share of supplier turnover can make supplier development easier. If the buyer is important to the supplier, the supplier may be more willing to invest time, resources, and management attention.
This can support joint improvement projects, quality development, sustainability work, process alignment, innovation, and cost reduction initiatives.
However, supplier development should be built on mutual value. A supplier that is dependent but financially weak may not have the resources to develop. A supplier that is important but poorly managed may become reactive instead of proactive.
The buyer should not only ask, “How much of their turnover do we represent?” The buyer should also ask, “Can this supplier use our business to become stronger, more capable, and more competitive?”
5. Market conditions
The right share of supplier turnover depends heavily on the supplier market.
In a market with many qualified suppliers, it may be less risky to keep a lower share. The buyer has alternatives, and the supplier is easier to replace.
In a market with few suppliers, high technical complexity, long qualification times, or limited capacity, the buyer may need a deeper supplier relationship. In those cases, a higher share of supplier turnover may be acceptable or even necessary.
For example, in a highly specialized category, the supplier may need volume commitment to justify investment in tools, people, capacity, or technology. In that situation, a higher share can support security of supply and supplier commitment.
Market context is therefore essential. The same percentage can mean different things in different categories.
How Kraljic’s Matrix changes the answer
Kraljic’s Matrix is useful because it helps buyers understand whether supplier turnover share should be viewed mainly as a cost issue, a risk issue, or a strategic relationship issue.
The four Kraljic categories each create a different interpretation.
Leverage items
For leverage items, the buyer has significant spend and there are several supplier alternatives. In this situation, a high share of supplier turnover can strengthen negotiation power, but the buyer should avoid unnecessary dependency.
The buyer can often use competition, tendering, and benchmarking to maintain pressure. A very high share may not be needed unless the supplier offers clear additional value.
For leverage items, the buyer should focus on commercial value, competition, and avoiding over-commitment.
Strategic items
For strategic items, the category has high business impact and high supply risk. Here, a higher share of supplier turnover may be acceptable if it supports long-term cooperation, innovation, capacity, or security of supply.
In strategic relationships, the buyer may intentionally become a key customer. But that relationship must be managed carefully through governance, performance reviews, risk monitoring, and joint development plans.
For strategic items, the question is not only whether the share is high. The question is whether the relationship is mature enough to handle that level of mutual dependency.
Bottleneck items
For bottleneck items, supply risk is high but spend may be relatively low. The buyer may represent a small share of supplier turnover and still face serious supply risk.
This is an important point. A low share does not always mean low risk. If the item is difficult to replace, technically unique, or supplied by only a few companies, the buyer may have limited influence even with critical dependency.
For bottleneck items, the buyer should focus on risk reduction, alternative sources, technical standardization, safety stock, or redesign opportunities.
Non-critical items
For non-critical items, both supply risk and financial impact are low. Share of supplier turnover is usually less strategically important.
The buyer should avoid spending too much management effort on detailed supplier dependency analysis unless there is a specific operational problem. The focus should instead be efficiency, process simplification, catalog buying, or standard terms.
For non-critical items, the key question is not supplier turnover share. The key question is whether the buying process is efficient.
Practical buyer example
Imagine that your company spends €3 million per year with a supplier. The supplier’s annual turnover is €12 million.
That means your company represents 25% of the supplier’s turnover.
At first glance, this may look high. But the right conclusion depends on the situation.
If the supplier provides a standard product in a competitive market, 25% may be unnecessary and potentially risky. The buyer may want to reduce dependency, introduce a second supplier, or negotiate better commercial conditions.
If the supplier provides a strategic component with limited alternatives, 25% may be acceptable. The buyer may intentionally be a key customer to secure capacity, influence innovation, and build long-term cooperation.
The tactical buyer should not stop at the percentage. The buyer should investigate:
- What category is this?
- How many alternative suppliers exist?
- How difficult would it be to switch?
- Is the supplier financially stable?
- Is the supplier investing in capacity and capability?
- Are we receiving the attention and performance expected from such an important customer?
- Would the supplier survive if our volume dropped?
- Would we survive if the supplier failed?
This is where procurement judgment becomes more important than a simple rule.
How this connects to the tactical procurement role
Share of supplier turnover is mainly a tactical procurement topic because it sits between day-to-day buying and long-term procurement strategy.
The tactical buyer often works with supplier selection, RFQs, negotiations, supplier evaluation, supplier development, and category-related decisions. In all these areas, supplier turnover share can influence the recommended approach.
A tactical buyer may use the concept when:
- Preparing a sourcing strategy
- Evaluating supplier risk
- Selecting suppliers after an RFQ
- Preparing for negotiation
- Reviewing supplier performance
- Planning supplier development
- Deciding whether to dual-source
- Assessing whether a supplier relationship is becoming too dependent
The operative buyer may notice symptoms, such as poor delivery performance or lack of supplier attention. The procurement manager may set policy and risk appetite. But the tactical buyer is often the person who turns the analysis into practical sourcing and supplier management actions.
Where this fits in the procurement process
Share of supplier turnover can be used in several parts of the procurement process.
Market analysis
During market analysis, the buyer should understand supplier size, market position, customer base, and financial stability. This gives context before deciding which suppliers to invite to an RFQ.
Supplier qualification
During supplier qualification, turnover share can help identify dependency risk. A supplier that is too small for the expected volume may still be capable, but the risk must be understood.
RFQ and supplier selection
During RFQ evaluation, the buyer should compare not only price and technical compliance, but also supplier fit. A supplier may offer an attractive price but become too dependent on the buyer’s volume.
Negotiation
During negotiation, turnover share helps the buyer understand relative importance. It can indicate whether the buyer has leverage, whether the supplier is likely to prioritize the business, and whether the commercial expectations are realistic.
Contract and implementation
During implementation, a high share of supplier turnover may require stronger governance, clear escalation paths, volume transparency, and risk monitoring.
Supplier management
During supplier management, turnover share should be reviewed together with performance, financial health, business continuity risk, and supplier development potential.
Common mistakes when using share of supplier turnover
Mistake 1: Treating 20% as a fixed rule
The 20% guideline is useful, but it is not universal. A buyer should not automatically reject a supplier because the share would be 22%, or automatically accept a supplier because the share is 18%.
The percentage must be interpreted together with category risk, market conditions, supplier capability, and the strategic importance of the relationship.
Mistake 2: Looking only at the buyer’s spend
The buyer’s spend is only one side of the equation. A €1 million spend may be small for a large global supplier but critical for a small local supplier.
Always compare your spend with the supplier’s total turnover, customer base, profitability, and capacity.
Mistake 3: Confusing importance with control
Being an important customer does not mean the buyer controls the supplier. Influence depends on many factors, including alternative customers, supplier margins, capacity constraints, technology ownership, and market demand.
A supplier may depend on your revenue but still control a critical technology or scarce capacity.
Mistake 4: Ignoring profitability
Turnover is not the same as profit. A buyer may represent a high share of supplier turnover but a low share of supplier profit if margins are poor.
This matters because suppliers prioritize business that is profitable, stable, and strategically attractive. A large but unprofitable customer may not receive the attention expected.
Mistake 5: Forgetting the supplier’s other customers
A supplier with one or two dominant customers may be more vulnerable than a supplier with a diversified customer base.
The buyer should understand whether the supplier is balanced or exposed. A supplier that depends heavily on a few customers may face instability if one customer changes direction.
Mistake 6: Ignoring switching difficulty
A low share of supplier turnover does not mean low risk if switching supplier is difficult. For bottleneck or strategic items, even a small spend can create serious operational exposure.
The buyer should always combine turnover share with switching cost, qualification time, technical complexity, and availability of alternatives.
Practical checklist for buyers
Use these questions when assessing share of supplier turnover:
- What percentage of the supplier’s turnover do we represent?
- Is this percentage increasing or decreasing?
- Is the supplier financially stable?
- How diversified is the supplier’s customer base?
- Are we important enough to receive proper attention?
- Are we so important that the supplier becomes dependent on us?
- Do we have alternative suppliers?
- How long would it take to switch supplier?
- Is the category leverage, strategic, bottleneck, or non-critical?
- Does the current relationship support our business objectives?
- Are we using our influence responsibly?
- Should we reduce risk through dual sourcing, contract terms, forecasting, or supplier development?
This checklist helps move the discussion from a simple percentage to a more complete procurement assessment.
Related course: Get to know Kraljic and his matrix
To understand share of supplier turnover properly, buyers need to connect the number to category risk and business impact. That is why Kraljic’s Matrix is a natural foundation for this topic.
The Learn How to Source course Get to know Kraljic and his matrix explains how procurement professionals can classify categories and adapt their sourcing approach depending on supply risk and financial importance.
This article applies that thinking to supplier dependency and turnover share. The course gives the structured foundation behind the method.
FAQ
What is share of supplier turnover?
Share of supplier turnover is the percentage of a supplier’s annual revenue that comes from one customer. In procurement, it is used to understand supplier dependency, buyer influence, and relationship risk.
How do you calculate share of supplier turnover?
Divide your annual spend with the supplier by the supplier’s annual turnover and multiply by 100. For example, if you spend €2 million and the supplier’s turnover is €10 million, your share is 20%.
Is 20% of supplier turnover always the right level?
No. The 20% guideline is only a rule of thumb. The right level depends on the category, supplier market, business risk, supplier capability, and strategic importance of the relationship.
What happens if a buyer represents too much of a supplier’s turnover?
The supplier may become too dependent on the buyer. This can create financial exposure, reduce supplier resilience, and increase business continuity risk if demand changes.
Can a high share of supplier turnover be positive?
Yes. A higher share can make the buyer a priority customer and support collaboration, innovation, capacity planning, and supplier development. But it must be managed carefully.
Is a low share of supplier turnover always safe?
No. A low share may mean the buyer has limited influence. For bottleneck or strategic items, even a small share can create high risk if the supplier is difficult to replace.
How does Kraljic’s Matrix help?
Kraljic’s Matrix helps the buyer understand whether the supplier relationship should be managed mainly for cost efficiency, risk reduction, leverage, or strategic partnership. This changes how the buyer should interpret supplier turnover share.
Conclusion
Share of supplier turnover is a useful concept in tactical procurement because it helps buyers understand the balance between influence and dependency. The common 20% guideline is a helpful starting point, but it should never replace procurement judgment.
A healthy supplier relationship is not only about being important to the supplier. It is about having the right level of influence, acceptable risk, strong performance, and a relationship that supports the buyer’s business needs.
The next practical step is to review your most important suppliers and calculate your share of their turnover. Then compare that number with category risk, supplier performance, market alternatives, and your sourcing strategy.
That is where the real procurement insight begins.
