Wednesday, March 11, 2026

Segregation of duties: a practical matrix for mid-size firms

Iratxe Gurpegui
Written by
Iratxe Gurpegui
5 min read
Segregation of duties: a practical matrix for mid-size firms

PME and Mid-size compliance teams often have the same uncomfortable reality: your policies say “segregation of duties”, but your operating model says “two people for six critical steps”. Then an auditor (internal, external, AFA-style review, ISO certification audit) asks a simple question: show me how you prevent one person from initiating, approving, and paying in the same workflow.

A practical segregation of duties matrix is the fastest way to move from intentions to evidence. Done well, it also reduces training fatigue because it replaces generic rules with role-based, process-based guardrails.

Why segregation of duties breaks down in mid-size firms

In theory, segregation of duties (SoD) is straightforward: separate initiation, approval, execution, recording, and review. In practice, small and mid-size groups in un into four predictable failure modes:

  • Role overload: the same manager is “business owner”, “budget approver”, and “invoice approver”.
  • Tool fragmentation: ERP approvals are separated, but vendor creation sits in a shared mailbox, and evidence sits in personal folders.
  • Matrix drift: the SoD matrix exists, but no one can prove it is enforced (access rights, workflow configuration, exception approvals).
  • Local variations: local sites apply the same principle differently, with inconsistent thresholds and unclear compensating controls.

SoD is not only an anti-fraud concept. For anti-corruption and competition compliance, it is also a program effectiveness signal: it shows you can prevent, detect, and escalate conflicts of interest, improper third-party onboarding, non-compliant discounts, and “friendly” approvals.

What “good” looks like for audits

The details vary by framework, but reviewers generally look for the same chain: risk scenario, control design (including SoD), evidence, testing, remediation.

The five-step method to build a segregation of duties matrix

This method is designed for teams with limited headcount, multiple countries, and frequent audits.

Step 1: Pick the processes that actually create exposure

Start with 6 to 10 processes where SoD failures create a plausible legal or regulatory risk, not only a theoretical risk.

A practical starter set for small and mid-caps:

Process

Typical exposure if SoD fails

Why it matters in audits

Third-party onboarding

Shell vendors, conflicted intermediaries, incomplete due diligence

Links to due diligence expectations and accounting controls

Purchase to pay (P2P)

Fake invoices, split payments, bypassed approvals

Core “books and records” integrity signal

Gifts, hospitality, travel

“Friendly” approvals, thresholds bypassed

Easy to test, often reviewed

Donations, sponsorships

Hidden benefits, local pressure, reputational risk

High scrutiny in anti-corruption programs

Sales discounts and rebates

Off-book benefits, side deals, distributor misuse

Relevant for anti-corruption and competition risk

Hiring, promotions, bonuses

Conflicts of interest, undue influence

Governance and culture indicator

Keep the first version narrow. A matrix that covers everything usually proves nothing.

Step 2: Define roles (not names) and map them to systems

Write roles the way your business operates, then map each role to:

  • The system(s) used (ERP, expense tool, CRM, procurement tool)
  • The permission set (create, approve, release, modify master data)
  • The evidence source (workflow log, access report, register entry)

Examples of role definitions that work well across France and Spain:

Role

Scope

What to avoid in the definition

Requester

Creates a purchase request or expense claim

“Anyone in operations” (too broad to audit)

Budget owner

Approves budget availability

Mixing budget approval with payment release

Procurement

Runs sourcing and issues PO

Owning vendor creation without controls

AP accountant

Processes invoices

Ability to create vendors and process invoices

Treasury

Releases payments

Approving their own beneficiaries

Compliance or legal reviewer

Reviews high-risk third parties, donations, sensitive spend

Being the operational approver by default

Step 3: Write “incompatible duty pairs” first

Instead of trying to fill a giant matrix immediately, start with a short list of non-negotiable conflicts that your auditors will recognize.

Use a table like this, and treat it as your SoD rulebook.

Duty a

Duty b

Why incompatible

Compensating control if separation is impossible

Create vendor (master data)

Approve vendor

Enables self-approval of a risky third party

Independent periodic vendor master review, with documented sampling

Create vendor

Process invoice

Enables fake vendor and fake invoice chain

Automated duplicate checks plus independent review of new vendors

Approve invoice

Release payment

Enables “approve and pay” without challenge

Dual payment release, or treasury release + post-payment review

Submit expense

Approve expense

Enables personal benefit without review

Manager approval enforced by system, plus audit sampling

Own contract negotiation

Own due diligence sign-off

Can “push” an intermediary through

Second-line review above thresholds or red flags

Configure approval workflow

Be beneficiary/requester

Can design a bypass

Change control with peer review and audit trail

This list is usually easier to agree on with finance, procurement, and IT than a full matrix.

Step 4: Build the matrix around “initiate, approve, execute, record, review”

Now you can translate the rulebook into a matrix per process. Keep it readable and enforceable.

Below is a practical example for third-party onboarding and payment, which is often a high-value audit area.

Step

Initiate

Approve

Execute

Record

Review

Vendor onboarding request

Business requester

Procurement or budget owner

N/A

N/A

Compliance or legal (risk-based)

Due diligence (risk-based)

Procurement

Compliance or legal

N/A

N/A

Compliance lead periodic QA

Vendor creation in ERP

AP or master data clerk

Finance manager

N/A

ERP record

IT access review quarterly

PO issuance

Procurement

Budget owner

Procurement

ERP record

Procurement manager sampling

Invoice processing

AP accountant

Budget owner

N/A

ERP record

Finance controller sampling

Payment release

N/A

N/A

Treasury (dual release if possible)

Bank file + ERP

Finance controller post-payment analytics

Two notes that matter in small and mid-size firms:

  • You do not need five different people. You need incompatible steps not held by the same person, plus a compensating control when headcount is tight.
  • “Review” is where many small and mid-size teams win audits. It is also where many fail because they cannot show evidence of a real review cadence.

Step 5: Create an exceptions register (and treat it as an audit element)

If exceptions are informal, they will be seen as control failures. If exceptions are governed, they can be accepted as proportional.

Use an exceptions register template like this:

Exception id

Process

Conflict

Reason

Compensating control

Owner

Start date

End date

Evidence link

EX-2026-001

P2P

Invoice approval + payment release

Small site, 2-person finance

Dual bank release + monthly post-payment review

Finance director

2026-02-01

2026-06-30

Folder or ticket reference

The “evidence link” can be a shared location, a ticket ID, or a control record, the key is that it is stable and retrievable.

Simple decision tree showing how to handle segregation of duties conflicts: identify conflict, can roles be separated, if yes enforce in workflow, if no document exception with compensating control, then test and review quarterly.

A decision rule for compensating controls (when you cannot segregate)

Auditors do not expect infinite headcount. They do expect that you recognize conflicts and reduce risk in a traceable way.

Use this decision rule to pick compensating controls that are credible:

If the same person must…

Minimum compensating control

What “good evidence” looks like

Create vendor and process invoices

Independent review of all new vendors for the period

Report of new vendors, reviewer sign-off, tracked findings

Approve and pay

Dual release at bank, plus post-payment analytics

Bank authorization log, monthly review memo with sample

Own due diligence and approval

Second-line spot checks based on risk triggers

Sampling plan, results, remediation actions

Configure workflows and submit requests

Change control with peer review

Ticket with approval, before/after config export

How to test SoD effectiveness (and prove it)

A matrix is control design. Audit readiness requires control effectiveness testing.

A lightweight quarterly test plan that works in most mid-size firms:

Test

Frequency

Sample

Pass criteria

Evidence to retain

Access rights review for incompatible permissions

Quarterly

All users with sensitive permissions

No unapproved conflicts, exceptions documented

Access report, reviewer sign-off, exception list

New vendor review

Monthly or quarterly

100% or risk-based sample

Due diligence present where required

Vendor list, check results, follow-ups

Payment run review

Monthly

1 to 2 payment runs

Dual release performed, anomalies investigated

Bank log, review checklist, anomalies notes

Gifts and hospitality approvals

Quarterly

Risk-based sample

Approvals follow thresholds, no self-approval

Register extract, sample testing sheet

If your evidence is spread across tools, build a repeatable way to collect it. For teams with internal tooling or API-based workflows, it can be useful to generate consistent test runs and logs using a local flow runner such as DevTools – local-first API testing & flow automation to record approval paths, export reviewable flows, and produce test reports that you can archive.

A short implementation checklist

  • Define the 6 to 10 in-scope processes and risk scenarios.
  • Agree on the incompatible duty pairs (the SoD rulebook).
  • Map roles to systems and permission sets, then identify conflicts.
  • Decide which conflicts are fixed by workflow, which require compensating controls.
  • Create the exceptions register and name an owner for each exception.
  • Set the first quarterly test plan and pre-book the review meeting.

If you do only one thing for audit readiness, do this: make sure every rule in your SoD rulebook has a corresponding evidence source.

How naltilia can help

If your main pain is not defining segregation of duties, but operationalizing it with evidence, Naltilia can help centralize and automate the work around risk and controls. Teams typically use it to connect SoD requirements to risk assessments, assign owners, track remediation actions automate data collection for control tests, and maintain audit-ready records across entities. It can also support structured workflows for approvals and policy updates so your matrix stays aligned with how the business actually operates. Contact us if you want to see how Naltilia works.

This article is general information, not legal advice.

About the Author

Iratxe Gurpegui

Iratxe Gurpegui

I've spent 20 years as a compliance and competition lawyer across Europe and Latin America, and throughout my career, I've seen firsthand how complex and costly regulations can hold companies back. But I've also learned that compliance doesn't have to be a burden, it can be a strategic advantage. My mission is to help companies harness the power of AI, transforming compliance into something faster, simpler, and most importantly, a real driver of growth for businesses.