Saturday 21 June 2025

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/ Why Choose an NSI Approved Company?

NSI is the UK’s leading UKAS accredited certification body within the security systems, manned security services and fire safety sectors. We are a not-for-profit organisation helping to protect homeowners, businesses and the general public through rigorous independent auditing of more than 1800 security and safety providers throughout the UK.

All NSI approved companies are regularly audited by our in-house, highly trained team of auditors to British and International standards, NSI Codes of Practice and certification schemes developed by Industry Bodies and Associations.

Experts in Security & Fire Safety

As a buyer you want to know your security and fire safety provider is reputable and trustworthy with the expertise to translate your needs into a solution that’s right for you.

Many insurers recognise NSI approved companies and the systems they install.  Your insurer may ask for a copy of the NSI Certificate of Compliance as proof that installation work was conducted by an NSI approved company. Check with your insurer whether having a security alarm system installed and maintained by an NSI approved company leaves you eligible to a discount on your insurance premium.

You can check which services an Approved Company holds approval for by using the NSI Company Finder. For example, if you are looking for a supplier of an NSI compliant intruder alarm system (for which your chosen installer will issue an NSI Certificate of Compliance) you will need to identify an installer who holds either NSI NACOSS Gold Approval or NSI Systems Silver Approval.

Experts in Security Services

NSI’s Security Services scheme covers a wide range of security activities, including Security Screening, Guarding, Keyholding, Door Supervision, Close Protection and many other specialist activities.

Technical Expertise and Quality

NSI approval is a highly respected and trusted hallmark in the security and fire sectors, demonstrating technical expertise and a reassuring quality of service.  Companies holding approval provide a range of services from intruder alarm and CCTV system installations to mobile / static guards and key-holding, fire alarms and life safety fire risk assessment.

Look out for the NSI hallmark of approval, it tells you a company is:


Technically Competent & Experienced
– working to relevant standards and NSI codes of practice, with managers having relevant technical and engineering experience

Professional – in the case of Gold approval operating a Quality Management System to ISO 9001

Trusted & Reputable – directors have the relevant business experience and all staff with access to sensitive information are security screened*.

All NSI approved companies are regularly checked during the audit for financial probity, insurance, contract management, contract infrastructure and management of personnel.

In choosing an NSI Gold approved company your provider will be progressive in its use of Quality Management Systems and have the relevant knowledge of standards to drive continual improvement in performance, efficiency and customer service.

Find an NSI approved company and check the services for which they hold approval, or ensure your existing company is genuinely approved now in the NSI approved company finder.

*Except fire specialist companies operating exclusively to BAFE schemes.