A Decade of the Modern Slavery Act: Progress, Challenges and the New TISC Guidance
Charlotte Kincaid
Senior Consultant
10 Apr 2025
About 9 mins
The UK Modern Slavery Act was praised as world-leading when it came into force in 2015, inspiring other countries such as Australia to enact similar legislation. Today, it faces criticism for lagging behind other more far-reaching transparency and due diligence legislation. New government guidance aims to address some of these concerns.
After 10 years of Modern Slavery Act (MSA) implementation, an estimated 122,000 people are living in modern slavery in the UK. Globally, too, this issue isn’t going away: on any given day 27.6 million people are in forced labour, an increase of 2.7 million from 2016.
In March 2025 the UK government issued updated guidance for organisations in scope of the Act. This provides much-needed clarity on what’s expected in companies’ annual modern slavery statements and practical advice to help businesses undertake meaningful action to tackle modern slavery. At twice the length of the original guidance, the updated guidance is a lot for businesses to digest.
This article explores lessons learned from the past 10 years, key changes to the guidance, what the updated guidance means for organisations reporting under the Act, and whether these changes could be a signal of evolution in legislation globally.
The journey so far – mandating transparency in supply chains for the first time
Modern slavery is often hidden in plain sight, in “ordinary” workplaces, and can cause irreparable harm to victims. Victims and survivors may endure violence, psychological abuse, unpayable debts or restrictions on their freedom of movement.
On top of this, the presence of modern slavery in an organisation’s supply chain or operations can have severe consequences to a business and its stakeholders. These can include reputational damage, the loss of business opportunities, restrictions on trading, increased insurance premiums and a negative impact on investment. What’s more, modern slavery poses a real risk to the global economy: if those in forced labour were brought into formal employment, this could potentially add £478 billion in global GDP.
Section 54 of the Act, known as the “Transparency in Supply Chains” (TISC) provision, was introduced to encourage businesses to proactively assess and address modern slavery risks. UK-based businesses with an annual turnover of £36 million or more are required to produce and publish a modern slavery statement each financial year. This statement, approved at board level, must detail the steps taken to mitigate modern slavery risks within operations and supply chains.
By advocating transparency, accountability and sustained progress, the law seeks to reduce the prevalence of modern slavery, as well as inspiring “a ‘race to the top’ culture where organisations aim to lead the way in tackling modern slavery”.
The business case for tackling modern slavery
Proactively addressing modern slavery offers significant business benefits. Companies committed to ethical practices can attract customers, investors and talent. Meanwhile, identifying and mitigating modern slavery risks strengthens supply chain resilience, helping avoid disruptions from scandals, legal issues or supply chain breakdowns.
This is crucial in an era of geopolitical uncertainty, where trade disputes, political instability, and economic sanctions can disrupt supply chains. Robust risk management strategies are essential to ensure smooth supply chain functioning and operational stability.
Modern slavery is a key component of the ‘S’ in ESG, and investors will closely watch businesses’ reactions to updated guidance. The new guidelines will increase data quantity and granularity, improving investor access which has long been called for. Given the likely increase in modern slavery risks under current geopolitical conditions, it will remain a key investment consideration – being able to demonstrate robust measures to tackle modern slavery may boost investor confidence.
The MSA’s first decade: achievements and limitations
Since its introduction, the MSA has faced ongoing criticism for its limited enforcement power and insufficient reporting requirements, which undermine its potential to deliver meaningful impact. This stands in stark contrast to more robust legislation, such as Canada’s Forced Labour and Child Labour in Supply Chains Act and the EU Corporate Sustainability Due Diligence Directive (CSDDD). Respectively, these laws mandate specific reporting obligations and require risk-based due diligence, setting higher standards for accountability.
Compliance with Section 54 has been mixed. In 2019, an independent review of the Act estimated that 40% of eligible companies are not complying with the legislation at all. A report by the Financial Reporting Council found that 12% of companies in a sample of 100 did not publish any modern slavery statement. The reasons for non-compliance are various, including uncertainty on which businesses are in scope, lack of awareness of what is legally required in the statement and perceived lack of consequence for non-compliance.
What impact has there been on the prevalence of modern slavery?
In the UK in 2022, potential cases of modern slavery reported through the National Referral Mechanism (NRM) reached almost 17,000 potential victims, an increase of 33% on the previous year and the highest levels since the NRM began in 2009. This reflects global trends. The most commonly referred nationals in 2023 were UK (25% of referrals), followed by Albanian and Vietnamese. Strikingly, 78% of UK nationals referred were children. Due to the hidden nature of modern slavery, these figures are likely to be an underestimate. This increase could be an indicator of better awareness and detection of modern slavery in the UK since the introduction of the law. There is evidence of improvement in how businesses are assessing and identifying modern slavery.
The 2024 CCLA Modern Slavery UK Benchmark reports that over 50% of the 110 companies included in the benchmark improved their score, a 6.5% increase on the previous year. This means they have improved their conformance with the law and have improved due diligence processes aimed at preventing modern slavery in their operations and supply chains. These build on improvements identified in the 2023 benchmark report, suggesting effective implementation.
A positive outcome of the law is a greater awareness of the critical need to collaborate with industry peers, NGOs, governments, suppliers and trade unions to effectively address modern slavery. This is because issues are most likely found further down the supply chain, so coordinating action amongst peers to leverage suppliers is key to driving change.
The updated guidance: understanding the new TISC requirements
Underlining the “spirit of the law”: The updated guidance underlines the importance of aligning with both the “letter” and “spirit” of the law. This means it provides practical recommendations on how to protect workers against modern slavery risks, as well as how to produce a compliance statement.
Aligning with international frameworks: It links reporting information with relevant parts of the OECD Due Diligence Guidance and United Nations Guiding Principles on Business and Human Rights (UNGPs), providing context on why these requirements are in place. This supports businesses who are already aligning with these frameworks to continue to do so, while providing efficiencies for companies to comply with other laws that also take these frameworks as their foundation, such as the CSDDD.
Practical advice: The guidance provides needed clarity on which organisations are in scope, which is especially helpful for those with complex structures. The guidance translates the legal text into practical insights with case studies to help businesses understand expectations and requirements and explains what is meant by ‘good’ and ‘best’ practice. The guidance provides a continuous improvement framework, demonstrating that compliance isn’t a box-ticking exercise; assessment and management are essential for resilience and improving working standards in supply chains.
Stakeholder engagement and partnership working is highlighted as a driver of effective action. The guidance details how stakeholders should be involved throughout due diligence processes to ensure measures to address modern slavery are effective.
Accountability is also emphasised, encouraging businesses to build governance structures to ensure senior-level responsibility for identifying, assessing and responding to modern slavery. This includes setting goals and KPIs, and tracking their implementation.
Encouraging transparency: The guidance references the UK’s Modern Slavery Statement Registry, launched in 2021, which aims to enhance transparency by encouraging companies to upload their annual statements to an online public repository.
Practical recommendations for businesses
So, what should businesses in scope of the MSA do next? Businesses should use the updated guidelines as a prompt to reassess current management systems and policies against the new guidance and its underlying frameworks.
- Think about how you can engage stakeholders to provide input on your review, including views from suppliers, employees and NGOs.
- Look at your governance structures and understand if there is appropriate senior-level oversight and accountability to ensure that any changes to your policies and processes are implemented effectively.
- Learn from what works and what doesn’t through setting up regular monitoring processes to understand the effectiveness of your efforts.
- Contribute to a culture of transparency and publish your statement on the Modern Slavery Statement Registry where it can be easily accessed by stakeholders.
Looking forward: the evolving landscape of supply chain transparency
The UK government is expected to introduce more changes over the course of this parliament in an effort to eradicate modern slavery. In January 2025, the government’s Joint Committee on Human Rights launched a new inquiry into forced labour in UK supply chains, assessing the effectiveness of legal and voluntary frameworks, including the Modern Slavery Act.
Several figures have also introduced additional legislation in parliament, such as Baroness Young of Hornsey, who introduced a bill on corporate due diligence in 2023, which they may continue to push for. With the Australian government expected to introduce changes to its own modern slavery law this year and the EU Forced Labour law coming into force in 2027, businesses in the UK and beyond should monitor changes to the legislative landscape carefully.
The Modern Slavery Act has had a profound impact on corporate behaviour over the past decade. Although there have been challenges and criticisms, the Act has driven improvements in awareness, transparency and accountability.
The recent updates to the TISC guidance don’t change the text of the law, which itself is still a long way from mandating supply chain due diligence. But the guidance does provide businesses with the tools and frameworks needed to enhance their efforts in tackling modern slavery. It also underlines the multiple benefits of adopting a mindset of continuous improvement, supporting resilience and enhancing business value.
The clearer alignment with international frameworks will be welcomed by businesses which are in scope of other transparency and due diligence legislation.
At Sedex Consulting we support businesses to strengthen their social and environmental risk management approach, aligned with international best practices and relevant legislation.
Talk to us to understand how we can work together to help you to understand your requirements and build resilience.
