The Corruption Perceptions Index Explained for AML Risk Assessments

The Corruption Perceptions Index, or CPI, is one of the most quoted country scores in compliance work, and one of the most often misused. It is published by Transparency International and is tempting to drop into a client risk matrix as a shortcut for "high-risk country". This guide explains how the CPI is calculated, what it measures and what it explicitly does not, and how to use it sensibly alongside other sources. It is based on Transparency International's own explanation of how CPI scores are calculated. We do not quote individual country scores, because they change each year and you should read the latest edition at source.

What the CPI measures

Transparency International describes the CPI score as the perceived level of public sector corruption. Each country receives a score from 0 to 100, where lower scores mean more perceived public sector corruption and higher scores mean a cleaner public sector. The score is built from surveys and assessments of experts and businesspeople, and covers matters such as bribery, diversion of public funds and state capture. The page we read refers to CPI 2025 as the most recent edition, covering 182 countries and territories, and says around 180 are included each year.

How the score is built

• Sources: a country's score combines data from at least three data sources drawn from 13 different corruption surveys and assessments. Transparency International names institutions such as the World Bank and the World Economic Forum among those that collect these sources.
• Minimum data: a country needs data from at least three of the 13 sources to be ranked. Transparency International says a country's absence from the list does not mean it is free of corruption, only that there is not enough data.
• Standardisation: each source's scores are rescaled using the global mean and standard deviation from CPI 2012 as the reference year.

What the CPI does not measure

This is the part that matters most for anti-money laundering (AML) work. Transparency International says the CPI does not capture citizens' direct experience of corruption, tax fraud, illicit financial flows, money laundering, private sector corruption or informal economies. A country can therefore score well on the CPI and still present money laundering risks, and the reverse also holds. Treat the CPI as one input on bribery and public sector integrity, not as a measure of a country's AML controls. For those, see our guide to the FATF recommendations, grey list and black list.

Comparing scores over time

Transparency International says scores can be compared across years only from 2012 onward, because the 2012 methodology update introduced the 0 to 100 scale. It also says changes are treated as statistically significant only when a majority of the underlying sources register them. In our view, a movement of a point or two between editions should not drive a change to a client's risk rating.

How accountants can use it: our suggestions

These are our suggestions, not regulatory requirements.

1. Use it for one question only. The CPI speaks to perceived public sector corruption, which is relevant to politically exposed persons, public procurement and bribery-linked source of funds. See our guide to politically exposed persons.
2. Combine it with other sources. Pair it with FATF lists, mutual evaluation reports, sanctions lists and your own supervisor's risk assessment. Our guide on how to read a mutual evaluation report explains one of them.
3. Record the edition. In your risk assessment, write down which year's index you used and the date you checked it.
4. Do not auto-escalate on a threshold. If your policy uses a score cut-off, explain why that cut-off is appropriate, and make sure it still lets staff apply judgement.
5. Look at the client, not just the country. The ownership structure, the source of funds and the services requested usually matter more. See our guide to customer due diligence in accountancy practices.

A worked example of sensible use

Suppose your firm is onboarding a client whose director holds a senior government post in another country. The CPI edition for that country is relevant context for the bribery and source-of-funds questions you ask about that director, which sit under enhanced due diligence for politically exposed persons. It is not evidence about the client itself, and it says nothing about whether the client's bank or the country's company registry is well supervised for money laundering. Write the CPI edition and the date you checked it on the file, then record separately what you learned from other sources about the person, the funds and the structure. If a reviewer later asks why the client was or was not escalated, the file should show a reasoned decision, not a score.

What we could not confirm

• The full list of 13 sources and how they are weighted, which the page we read did not set out in detail.
• How the averaging step works after standardisation, which Transparency International does not describe on that page.
• Whether your supervisor expects any particular index to be used. Check your supervisor's guidance.

Frequently asked questions

Does a low CPI score mean a country has a money laundering problem?

Not necessarily. Transparency International says the CPI does not measure money laundering or illicit financial flows.

Can I compare this year's score with 2010?

Transparency International says scores are comparable only from 2012 onward.

What if a country is missing from the index?

It means there is not enough data, since a country needs at least three of the 13 sources to be ranked. It does not mean the country is low-risk.

This guide is general information, not legal advice.