Master Key System Types
Primarily there are two types of systems.
Trusted master key system support
Speak to an MLA accredited locksmith team with in-house planning, documented suite records, and practical support before and after installation.
Master locksmiths with BSI accreditation
MLA approved locksmiths, BSI certified key systems, and independently audited security standards.
Featured guides
We have written a lot of information about master key systems, but don't get 'lost' in the detail - just call us or email us for a down to earth expanation and guidance.
Restricted Key Systems
Patented profiles, controlled ordering, and copy-prevention. Ideal when key control matters.
Key Control Policies for Organisations
Ordering authorisation, issuance, returns, audits, contractors, and incident response.
All system type pages
Technical and operational pages that support master key design, governance, and long-term maintainability.
Restricted Key Systems
Patented profiles, controlled ordering, and copy-prevention. Ideal when key control matters.
High-Security Master Key Systems
For sensitive zones: estates, labs, NHS areas, MOD-style risk profiles, and critical infrastructure.
Mechanical vs Electronic Hybrid Systems
When pure mechanical is best, and when hybrid access control makes sense operationally.
Key Hierarchy Design Explained
GMK/MK/SMK/CK, role keys, contractor access, and practical hierarchy examples.
Key Control Policies for Organisations
Ordering authorisation, issuance, returns, audits, contractors, and incident response.
How to Replace a Lost Master Key
Risk-based response for SMK/MK/GMK loss: selective rekey, redesign, or emergency action.
How to Audit Outdated or Unknown Key Suites
Turn mystery keys into a documented, controllable hierarchy that can be maintained and expanded.
Need action, not reading?
These pages are built for time pressure: quotes, expansions, lost keys, and urgent rekeying.
Get a Master Key System Quote
Fast route to a quote: door list, tiers, cylinder types, timeline.
Expand Your Existing System
Stabilise legacy suites and add doors safely against the plan.
Replace Lost Keys in an Existing Suite
Controlled replacement based on tier and exposure.
Emergency Rekeying for Master Key Suites
Time-critical options for lost masters and exposed sites.
Convert Your Building to a Master Key System
Replace fragmented locking with a structured, controlled hierarchy.
Planning a master key system?
Send a door list or tell us what you’re trying to control. We’ll propose a hierarchy, recommend key control, and quote supply and install.
Prefer to talk?
Phone: 01296 752080
Email: info@lockandkey.co.uk