Understanding the B2B buying process

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In consumer markets, buying decisions can be impulsive, emotional, or shaped by brand perception. B2B markets operate differently. Purchases are often larger, more complex, and frequently tied to long-term outcomes. Yet the process is not purely rational. It combines organisational priorities with the motives of the individuals involved. Understanding how this process unfolds is crucial for any supplier seeking to win and retain business customers.

More Than One Type of Decision

Not all business purchases are equal. Marketers and procurement specialists often classify them into three main categories.

New buy – The organisation is sourcing a product or service for the first time. The risks are higher, and suppliers must establish trust from scratch.
Modified rebuy – The company has some experience, but the requirements are changing. Perhaps they want a new contract structure, better pricing, or an additional feature. This presents an opportunity for alternative suppliers to compete.
Straight rebuy – Routine purchases from existing suppliers. Once a supplier has proved reliability, the customer is unlikely to switch unless a severe problem arises.

This matters because the supplier’s role changes depending on the situation. Winning a new buy requires education and credibility. Securing a rebuy requires consistency, responsiveness, and effective relationship management.

The Weight of Significance

Two factors shape every business buying process: purchase significance and buying organisation experience. A high-value IT infrastructure project for a UK bank may involve months of consultation, multiple decision makers, and rigorous procurement procedures. Ordering routine office supplies is of low significance and low risk, often handled automatically through established suppliers. The Chartered Institute of Procurement and Supply reports that UK public sector contracts can take over a year from tender to award when the stakes are high. Suppliers must be prepared for long sales cycles. Once selected, switching costs make relationships more stable.

How Buyers Now Research and Decide

The way business buyers research has changed considerably. According to Gartner, B2B buyers now spend only 17 per cent of their total buying time meeting with potential suppliers. When comparing multiple suppliers, the time spent with any single sales representative may be as little as five or six per cent. The rest is spent on independent research, internal discussions, and consensus building.

This shift has implications for how suppliers position themselves. If buyers are forming views and shortlists before making contact, being visible and credible during that research phase becomes essential. It also means that sales conversations, when they happen, carry greater weight. Buyers arrive with specific questions and expect substantive answers.

Loyalty and Switching Costs

Once a supplier is chosen, loyalty can develop. This is not just emotional loyalty but structural loyalty. The cost of switching can be high in terms of time, money, and operational disruption. Many NHS trusts continue to work with the same medical equipment providers year after year because changing would mean retraining staff, re-certifying equipment, and managing supply chain risks.

For suppliers, this creates both opportunity and danger. Secure the contract, and you have stability. Lose it, and it may be years before another chance emerges.

That said, loyalty should not be taken for granted. Research suggests that poor customer experience remains one of the primary reasons buyers consider switching, even when switching costs are high. Consistent service and responsiveness matter throughout the relationship, not just during the sales process.

Marketing’s Role Alongside Sales

Traditionally, business buying was seen as the domain of sales and account management. Marketing was often underdeveloped in B2B, as it was assumed to be less relevant because relationships were typically one-to-one. That view no longer holds. Marketing plays a vital role by building awareness and credibility before the sales conversation begins, providing research and segmentation to help target the right prospects, creating value propositions that reflect the drivers of efficiency, growth, and compliance, and supporting account teams with content that demonstrates insight and thought leadership.

A good example is Sage, the UK software company. Its marketing campaigns focus not on software features but on business outcomes such as productivity, compliance with HMRC requirements, and support for SMEs. By the time a prospect speaks to sales, they already understand the value Sage brings.

Understanding the DMU

The Decision Making Unit is central to B2B buying. Unlike consumer purchases, which are usually individual decisions, business buying involves a team with distinct roles.

Users. The people who will operate the product or service or be affected by it.
Influencers. Technical experts or consultants who advise on specifications.
Buyers. Procurement professionals who handle negotiations.
Deciders. Senior managers or directors who approve budgets.
Gatekeepers. Those who control access to decision makers, such as PAs or IT administrators.

One person may play several roles, but dynamics matter. Suppliers who identify the DMU and each member’s values are more likely to build consensus.

The Challenge of Buying Group Alignment

According to Gartner, a typical buying group for a complex B2B solution includes six to ten decision makers. Each has distinct priorities, concerns, and information sources. Reaching an agreement in such a group is rarely straightforward.

Gartner’s research found that buying groups reaching consensus are 2.5 times more likely to report a high-quality deal. The message for suppliers is clear: instead of relying on a single champion within the organisation, effective selling means helping the entire group align. This could involve providing materials to address stakeholder concerns, facilitating discussions, or simply being patient as the group decides.

The UK Picture

According to HM Treasury’s Public Expenditure Statistical Analysis 2025, gross spending on public sector procurement reached £434 billion in 2024/25 across the UK. This represents an increase of £19 billion on the previous year. Health, education, and social protection account for the largest shares of this spending.The Procurement Act 2023, effective February 2025, changes how public bodies buy goods and services. The Act seeks to simplify procedures, increase transparency, and lower barriers for small suppliers. For businesses selling to the public sector, understanding these changes is essential.

Beyond the public sector, UK businesses report growing procurement complexity. Regulatory demands, sustainability, and increased due diligence all extend evaluation periods. For SMEs, the lesson is to prepare fully. Understanding the buying process distinguishes between being shortlisted and ignored.

What This Means for Suppliers

To navigate the business buying process successfully, suppliers need to identify whether the situation is new, modified, or routine, assess the significance of the purchase and the buyer’s level of experience, map the DMU and understand each stakeholder’s agenda, and utilise marketing to establish credibility and gain insight before the sales call.

They should also consider how buyers research before making contact. If your website, case studies, and thought leadership content do not answer the questions buyers have during their independent research phase, you may never make it onto the shortlist. The sales conversation, when it comes, should build on a foundation of credibility already established.

This is not about playing the system. It’s about showing you help customers achieve their goals, making you a lower-risk, higher-value choice.

A Note for Business Leaders

For many growing businesses, the challenge is not understanding these principles in theory but applying them in practice. How do you map the DMU for your target customers? What content will resonate during the research phase? How should marketing and sales work together when resources are limited?

These are questions a fractional CMO can help you answer. If you would like to explore how strategic marketing leadership could support your B2B growth, I would welcome a conversation.