You cannot save money if you do not know where you are spending it. A beginner's guide to spend categorization.
The data exists. Somewhere in your finance systems, there are records of every pound spent with every supplier over years. Purchase orders, invoices, payment records—the raw material for understanding your spending sits waiting to be analysed.
Yet most organisations make strategic decisions about suppliers, categories, and procurement priorities based on incomplete information, gut feeling, and the opinions of whoever speaks loudest. The data that could inform those decisions remains locked in transactional systems, never converted into strategic insight.
What Spend Analysis Actually Is
Spend analysis is the process of collecting, cleaning, categorising, and analysing procurement expenditure data to answer strategic questions. What are we actually spending? With whom? On what? How has it changed? Where are the opportunities?
The concept is simple. The execution is harder than it appears. Data comes from multiple systems in inconsistent formats. Supplier names are spelled different ways. Categories are applied inconsistently or not at all. What should be straightforward analysis becomes data archaeology.
But the effort is worth it. Organisations that genuinely understand their spend make better decisions—about negotiations, consolidation, risk management, and strategic direction. Those that don't are flying blind.
The Data Challenge
The first obstacle is always data quality. Procurement data in most organisations is messy, incomplete, and inconsistent.
Multiple systems hold different pieces of the picture. Purchase orders in the ERP system. Invoices in accounts payable. Credit card transactions in a separate platform. Expense claims in yet another. Combining these into a coherent view requires integration effort.
Supplier identification is particularly problematic. The same supplier might appear as "ABC Ltd," "ABC Limited," "A.B.C. Company," and "ABC" across different transactions. Without normalisation, spend is fragmented and analysis is unreliable.
Category coding is often poor or absent. Transactions may have generic codes that don't distinguish between fundamentally different purchases. Or they may have no category at all, leaving analysis to guess based on supplier type or description fields.
Time must be invested in data cleaning before analysis yields reliable insight. This is unsexy work, but it's essential. Shortcuts here produce misleading conclusions.
The Category Dimension
Spend analysis organises expenditure into categories—a taxonomy that groups similar purchases for analysis and management.
Standard taxonomies exist. UNSPSC, NAICS, and proprietary frameworks from consultants and software vendors provide structures that work across industries. Adopting a standard enables benchmarking against peers and reduces the effort of building your own.
Customisation is usually necessary. Standard taxonomies may not reflect your industry's specific categories or how you want to manage your supply base. The framework should serve your management needs, not force you into inappropriate structures.
Hierarchical structure enables drill-down. High-level categories like "IT Services" break down into sub-categories like "Software Development," "Cloud Hosting," and "Support Services." Analysis can operate at appropriate levels of detail for different purposes.
Consistent application matters more than perfect structure. A simple taxonomy applied consistently provides better insight than a sophisticated taxonomy applied inconsistently. Get the discipline right first; refine the categories later.
The Questions Spend Analysis Answers
Good spend analysis illuminates strategic questions that were previously answered by assumption.
Consolidation opportunities emerge when you see the same category spread across dozens of suppliers. Why are we buying office supplies from 47 vendors? What would consolidation to two or three enable in terms of leverage and efficiency?
Price variation reveals negotiation opportunity. If different parts of the organisation pay different prices for identical items, there's value in standardisation. Even within single supplier relationships, price consistency can be evaluated.
Category prioritisation becomes data-driven. Which categories represent the largest spend? Which have the most suppliers? Which have changed most over time? These patterns indicate where procurement effort should focus.
Supplier dependency becomes visible. How much spend is concentrated with single suppliers? What would happen if they failed? Spend analysis reveals concentration risks that operational teams might not see.
Trend analysis shows trajectory. Is spend in this category growing? Shrinking? Becoming more or less consolidated? Understanding direction informs forward strategy.
From Analysis to Action
Insight without action is just expensive curiosity. Spend analysis should drive decisions.
Category strategies derive from analysis. Understanding the current state—spend levels, supplier landscape, price variation—informs the target state and the path between them. Analysis without strategy is incomplete; strategy without analysis is unfounded.
Sourcing priorities follow from opportunity sizing. If analysis shows £2 million potential savings in one category and £200,000 in another, resource allocation should reflect the difference.
Performance monitoring uses analysis as baseline. After category interventions, has spend reduced as expected? Has consolidation progressed? Analysis becomes the measurement tool, not just the diagnostic.
Stakeholder communication is enabled by clear data. "We're spending £5 million with 47 office supplies vendors at prices varying by 40%" is a more compelling opening than vague concerns about fragmentation.
Building the Capability
Sustainable spend analysis requires ongoing capability, not just one-time projects.
Technology investment is usually necessary. While basic analysis can be done in spreadsheets, scale and complexity quickly exceed spreadsheet capabilities. Purpose-built spend analysis tools handle data volumes, automate categorisation, and provide visualisation that manual approaches can't match.
Data discipline must be institutionalised. If data quality deteriorates after initial cleanup, analysis becomes unreliable again. Ongoing attention to supplier master data, category coding, and system integration maintains analytical foundation.
Skills matter. Interpreting spend data and translating it into strategic recommendation requires analytical capability that not all procurement teams possess. Investment in people—through hiring or development—enables effective use of analytical tools.
Refresh cycles keep analysis current. Spend patterns change. Suppliers change. Strategies evolve. Analysis performed once becomes stale. Regular refresh—quarterly or monthly—maintains relevance.
The Strategic Shift
Organisations with mature spend analysis capability operate differently from those without.
Decisions are evidence-based. Instead of debating what might be true, stakeholders examine what the data shows. This changes conversations from opinion to fact, from assertion to investigation.
Opportunities are identified proactively. Instead of waiting for problems to surface, analysis reveals opportunities before they're obvious. The organisation is proactive rather than reactive.
Accountability becomes possible. When baselines are clear and measurement is reliable, people can be held accountable for results. Vague claims give way to specific performance against specific targets.
This transformation doesn't happen overnight. It requires investment in data, technology, skills, and processes. But organisations that make the investment consistently outperform those that continue relying on incomplete information and instinct.
Spend analysis isn't glamorous. It's foundational. Every other aspect of strategic procurement—category management, supplier development, risk management, value creation—depends on understanding what you're actually spending. Start there.