Quick answer: Security spend looks predictable because the base contract is priced on headcount and hours. What actually drives cost is overtime, holiday cover, event security, and emergency callouts, all billed as separate line items that rarely get classified consistently. Until those lines are grouped properly, the real cost of a security contract stays invisible.
The base contract is the easy part
Headcount times hourly rate is simple to check. It's also a small part of the real cost. The variable layer, overtime, holiday cover, event days, short-notice callouts, is where the actual budget pressure comes from, and it's billed in whatever format the supplier finds convenient.
Why overtime and callouts hide in plain sight
A callout invoice might say "additional cover, site X, 4 hours." The same event at another site might say "emergency response." Same cost driver, different description, no way to compare them until someone classifies both the same way.
What happens once it's classified properly
You can finally answer the questions that actually matter: which sites drive disproportionate overtime, which suppliers price emergency cover fairly, and whether your contract's base rate still reflects how the service is actually being used.
Pearstop classifies every security invoice line, including the variable cover that never fits neatly into the base contract, so you can see the real cost of guarding a site, not just the headline day rate.

Stephanie Wiechers
CEO & Co-founder, Pearstop
Stephanie leads Pearstop's go-to-market and strategic direction. She works directly with procurement and FM leaders across Europe to understand how data quality affects margins, contracts, and AI readiness.
LinkedIn →Further reading
Why a general AI tool failed our classification problem
A general-purpose AI tool hallucinated categories at volume and lost consistency across thousands of lines. The tool was asked the wrong question.
Read more →Data ManagementOne spend report, three leaders, three different needs
A CFO, a head of procurement, and a commercial director read the same spend report and reach three different conclusions. Here is why.
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