NSI Company Finder

NSI company finder data is the certified universe of UK and Irish security and fire safety firms behind the insignia buyers look for on an alarm quote. The National Security Inspectorate - trading as Insight Certification Ltd, headquartered at Sentinel House in Maidenhead - describes its public finder as listing over 2,000 approved companies, and the register reaches well beyond intruder alarms.

Filtering runs two ways at once. By approval route: NSI Gold, NSI Silver, NSI CerticCS for the Republic of Ireland, and SIA ACS. By scope family: Security Systems (intruder and hold-up alarm systems, access control, CCTV surveillance, detector-activated CCTV to BS 8418, scaffolding alarms); Fire Safety Services (BAFE scopes including fire detection and alarm systems); Guarding Services (keyholding and alarm response, door supervision, close protection, security guarding, cash and valuables transport); Alarm Monitoring (alarm receiving centres, lone worker monitoring, remote video response centres); plus specialist services and out-of-UK CerticCS categories.

Region filters cover all 49 UK police forces plus dedicated guarding and fire regions, so a question like “every Gold-tier alarm receiving centre whose certified scope touches the Metropolitan Police area” is a lookup, not a research project. Each returned record carries a stable GUID, the company's full address and geocode, its public contacts, and the certified scopes it holds. Get a sample of this dataset →

One record per approved company, exactly as a delivery arrives:

CompanyID     : 8D803485-3461-44CE-A376-B04400A676D2
CompanyName   : BHP Alarms Ltd          ApprovalType : NSI CerticCS
Schemes       : CerticCS ARC | CerticCS Electronic Security
Address       : 20 Balliniska Road, Springtown Industrial Estate,
                Londonderry, County Londonderry BT48 0LY (GB)
Email         : sales@bhpalarms.com    Phone : +442871262757
Website       : www.bhpalarms.com      Lat/Lon : 55.0172 / -7.33053

ApprovedServicesOffered (per certified scope):
  scope        : Design, Installation and Maintenance of Intruder and Hold Up Alarm Systems
  region_group : <police-response region group>
  regions      : <covered police regions>

Read what the single row already proves. A GUID fixes the firm's identity, so joins survive company renames and re-registrations. The address arrives pre-split into street, town, county, region, postcode and country code, and it arrives geocoded - 55.0172, -7.33053 puts this Derry firm on a map and inside a radius query without a geocoding bill of its own. Two certification schemes travel side by side on one company: an alarm receiving centre approval alongside electronic security, which is how dual-discipline operators actually look in the register.

The deepest structure sits in ApprovedServicesOffered, where each certified scope carries its response-region group and the police regions it covers - the detail that turns “who installs alarms in Northern Ireland” into “whose intruder-alarm certification is valid for police response in the PSNI area”.

Eight fields define every record, and all eight were verified against live register records during the August 2026 research pass - the dictionary below is the complete delivery schema, not a subset:

CompanyID anchors identity. The seven-part address group locates the firm. Email / Phone / Website carry the public contact surface. Latitude / Longitude make distance queries native. ApprovalType splits the four approval routes, Schemes itemizes the certifications held, and ApprovedServicesOffered goes one level deeper still - scope by scope, region group by region group. Nothing sits in an on-request tier because nothing was left unconfirmed.

• Geography - the United Kingdom, with the Republic of Ireland covered through the CerticCS route. Filtering works at three depths: all 49 UK police forces, dedicated guarding and fire regions, or postcode-distance search for radius questions.
• Temporal - current certification status as published. This is a standing register of who holds approval now, not a historical archive; teams needing lapse-and-renewal trajectories start the snapshot series immediately and let the daily-to-hourly cadence accumulate the history cheaply.
• Granularity - one record per approved company, over 2,000 in aggregate, each carrying its schemes plus per-scope service detail with covered police regions.

The honest boundary: this is the certified floor of the market, and uncertified operators sit outside it by construction. That is a feature more often than a gap - penetration analysis, channel-quality scoring and risk screening all want a clean denominator, and “holds current NSI approval” is about as clean as the industry offers.

API, files, or your warehouse. Daily, weekly, or hourly.

You pick the channel and the cadence; the eight-field dictionary above travels unchanged through all of them. Rows arrive cleaned and typed - addresses pre-split, coordinates parsed, schemes and scopes normalized into queryable form - so vendor-vetting logic becomes a WHERE clause instead of a parsing project. The set joins cleanly to firmographic tables on CompanyName and geocode, and to our SSAIB companion set when a job needs both certifiers' universes. Cadence changes are a settings conversation, not a re-integration project, and a scoped sample comes first either way. Get a sample of this dataset →

• Alarm distributor networks and monitoring stations qualify subcontracted installers across a whole bench at once - approval tier, certified scope and police-response coverage per firm, rather than one manual lookup at a time.
• Private equity and corporate development teams map acquisition and roll-up candidates across the UK and Irish installation base, using approval tier as a capability proxy.
• Compliance and procurement teams document that every contracted installer held current certification at engagement - an auditable artifact rather than a screenshot.
• Market researchers and consultants size the installation and monitoring market from its certified floor, segmenting by region and discipline.
• Sales and growth teams build territory plans from where certified firms concentrate, prioritizing police-force regions by density rather than gut feel.

Deeper application notes sit on the competitive intel product teams, sales growth teams and market researchers pages.

Competitive intelligence and product teams get the cleanest public read on rival capacity: which competitors hold Gold-tier approval, which hold monitoring-centre certifications, and where their certified scopes touch which police regions. Sales and growth teams turn the register into partner-recruitment territories without assembling spreadsheets region by region. Investors and quant researchers frame consolidation theses on a defined population of certified firms. Data scientists adopt the CompanyID GUID as the entity spine that incident, permit and firmographic files hang off. Developers and builders wire automated vendor-vetting into procurement flows on a fully verified eight-field schema. Across all six, the constant is the same: a register that answers “who is certified, for what, and where” completely beats a wider source that answers it vaguely.

Three things, all knowable upfront. First, the register is a point-in-time picture - “over 2,000 approved companies” is NSI's own descriptive figure rather than a published running count, and your sample returns the populated rows for whatever tiers, scopes and regions you name, converting that estimate into a number you own. Second, coverage is the current certification state, so longitudinal questions need the snapshot series started now. Third, the dictionary is complete as delivered - all eight fields were verified against live records in August 2026 - so scope your integration around the constants above rather than holding budget for a hidden on-request tier.