Service 03 of 11
Outsourced & Co-Sourced Internal Audit Services
Internal audit capacity exactly when you need it. We run the whole function, join your team for specific audits, carry out audits on demand, or provide an interim Head of Internal Audit.
- Models
- Outsourced, co-sourced or interim
- Reports to
- Your audit committee
- Scales with
- Your risk-based audit plan
- Typical audits
- Procurement, payroll, inventory, projects
Overview
What is outsourced, co-sourced and interim internal audit?
Outsourced internal audit means an external provider delivers your internal audit function and reports to your audit committee. Co-sourcing means the provider works alongside your in-house team, adding capacity or specialist skills for particular audits. Interim support provides a Head of Internal Audit during a vacancy, leave or restructure.
All three models give you access to experienced auditors without the fixed cost, recruitment time and retention risk of building a full in-house team, and they can be scaled up or down as your risks change.
What it stands for
Who it’s for
Flexible audit resource without the overhead
A full in-house team is not always practical or affordable. Outsourcing and co-sourcing give you experienced auditors and specialist skills, scaled to your plan.
- Organisations without an in-house internal audit team
- Audit teams needing extra capacity or specialist skills
- Functions covering a vacancy, leave or restructure
- Boards wanting a specific area audited independently
How it works
From audit plan to closed actions
-
Stage 1
Plan
We agree the annual plan or the scope of individual audits with management and the audit committee.
-
Stage 2
Audit
We carry out walkthroughs, control testing and data analysis, keeping management updated throughout.
-
Stage 3
Report
We agree findings with management, with clear action owners and dates, and present them to the audit committee.
-
Stage 4
Track
We follow up agreed actions and report progress so issues are actually closed.
Experienced auditors, exactly when you need them, without the overhead of a full team.
What you receive
Audits that lead to action
Every deliverable is tailored to your organisation and written for the people who will use it.
Risk-based audit plan
Agreed with the audit committee.
Audit reports
Clear findings, ratings and agreed actions.
Action tracker
Owners, dates and follow-up status.
Committee reporting
Regular summaries for the audit committee.
Annual opinion
Overall view on governance, risk and control.
Interim leadership
Head of Internal Audit cover when needed.
Benefits
The value we add
Lower fixed cost
Pay for the audits you need rather than a permanent team.
Specialist skills
Access to experience you could not justify hiring full time.
Scalable
Increase or reduce coverage as risks, budgets and priorities change.
Fresh perspective
An external view that challenges assumptions and spots blind spots.
Continuity
Cover during vacancies, leave and change, so the plan stays on track.
Fast mobilisation
Experienced auditors can start quickly with proven methodology.
Senior-led
Delivered by chartered and certified professionals (ACA, ACCA, CIA).
Fixed fee
Scope and price agreed in writing before work starts.
Standards-aligned
Methodology aligned to the IIA Global Internal Audit Standards.
Frequently asked questions
Outsourced, Co-Sourced & Interim Internal Audit: your questions
How much does outsourced internal audit cost?
It depends on the number and complexity of audits in your plan. We price per audit or as an annual plan, agreed in writing before work starts.
What is the difference between outsourced and co-sourced internal audit?
Outsourced means we deliver the internal audit function for you. Co-sourced means we work alongside your in-house team, adding capacity or specialist skills for specific audits.
Which areas can you audit?
Typical audits include procurement, contracts, payroll, inventory, expenses, capital projects, revenue and operational processes. We agree the plan based on your risks.
Can you provide an interim Head of Internal Audit?
Yes. We can lead your function on an interim basis during a vacancy, leave or restructure.
How is it priced?
Either a fixed fee per audit or an agreed fee for the annual plan, set out in writing before work starts.
Page last updated 3 November 2026
Outsourced, Co-Sourced & Interim Internal Audit by sector
- Corporates & listed companies
- Private & family-owned businesses
- Public sector & local government
- Housing associations
- Education
- Charities & not-for-profit
- Healthcare & primary care
- Construction, real estate & energy
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