How many copies of your house key exist? Who has them? Are you certain?
Most people can’t answer these questions with confidence. Over years of normal life—lending to friends, giving to family, providing to tradespeople—key copies multiply. Control erodes. Security degrades invisibly.
Key control means knowing exactly who can enter your home and maintaining the ability to revoke that access. Establish control by documenting who has keys, limiting distribution, using restricted key systems where appropriate, and changing locks when key whereabouts become uncertain. If you can’t account for all copies, you don’t have control.
Why Key Control Matters
The Invisible Vulnerability
Your lock may be excellent. Your door may be reinforced. But if copies of your key are circulating with people you’ve forgotten about, none of that matters.
Key control failures don’t announce themselves. You won’t know you’re vulnerable until something happens—or until you honestly count the keys.
Who Might Have Keys?
In a typical household over five years:
- Family members (some no longer living there)
- Ex-partners (possibly from relationships ago)
- Friends given emergency access
- Neighbours for pet feeding or plant watering
- Cleaners (current and previous)
- Tradespeople who needed access
- Dog walkers, nannies, carers
- Estate agents (if you ever sold or let)
- Previous owners’ contacts (who may still have copies)
Each represents a potential copy—and each copy may have been copied again.
Establishing Key Control
Step 1: Audit Current Distribution
Create a simple list:
| Person | Date Given | Reason | Status |
|---|---|---|---|
| Sarah (daughter) | 2019 | Family | Active |
| Mike (neighbour) | 2021 | Cat sitting | Should recover |
| Previous cleaner | 2020 | Weekly access | Unknown |
| Current cleaner | 2023 | Weekly access | Active |
Be honest. Include everyone you can remember. Accept that there are probably more.
Step 2: Assess Current Risk
For each key holder, ask:
- Do they still need access?
- Do I trust them completely?
- Would I know if they copied the key?
- What changed since I gave it to them?
Step 3: Recover or Replace
For each unnecessary key:
Option A: Request return
- Appropriate for ongoing relationships
- No guarantee copies weren’t made
- Polite but not definitive
Option B: Change locks
- Definitive solution
- Necessary when keys can’t be recovered
- Fresh start with documented control
The Fresh Start Approach
Sometimes the only way to establish control is to assume it’s lost and start over.
When to Reset
Consider a lock change if:
- You’ve lost track of key distribution
- Multiple people with unknown key status
- Major life changes (divorce, new property, tenant changeover)
- Any incident that suggests key misuse
- Keys lost in identifiable circumstances
The Reset Process
- Change all exterior locks on the same day where possible
- Create new key inventory documenting all copies
- Distribute minimally - only to those who genuinely need access
- Establish new rules for future distribution
This is exactly what should happen when moving to a new property—but applies any time control has degraded.
Ongoing Key Management
The Distribution Decision
Before giving anyone a key, ask:
- Do they genuinely need unsupervised access?
- For how long will they need it?
- Can alternatives work instead? (being present, smart lock, key safe)
- Am I willing to change locks when this ends?
Record Keeping
Maintain a simple record:
- Who has keys
- When they received them
- Why they have access
- When to review (annual minimum)
Store this securely (not on a note by the keys).
Annual Review
Once a year:
- Review your key holders list
- Recover keys no longer needed
- Consider whether circumstances warrant lock change
- Update records
Restricted Key Systems
For maximum control, restricted keys prevent unauthorised copying.
How They Work
- Blanks are proprietary and not commercially available
- Copies require authorisation from the registered owner
- Dealers verify identity before cutting
- Creates a paper trail of all copies
Who Benefits
Restricted keys make most sense for:
- Those giving keys to multiple people
- Landlords with frequent tenant turnover
- Anyone wanting verification of key control
- Properties with high security requirements
The Trade-offs
Advantages:
- Complete copy control
- Authorisation required for new keys
- Paper trail of distribution
- Psychological deterrent
Disadvantages:
- Higher initial cost
- Inconvenience if you need copies urgently
- Relies on dealer compliance
- Not all systems equally secure
Alternatives to Physical Keys
Smart Locks
Replace key control with code control:
Advantages:
- Issue temporary codes
- Revoke access remotely
- See who accessed when
- No physical keys to copy
Disadvantages:
- Technical failures possible
- Battery/power dependent
- Codes can be shared
- May not meet insurance requirements
Key Safes
External lockboxes for key storage:
Best for:
- Emergency access backup
- Carer access where you control the code
- Situations where key distribution must be limited
Cautions:
- Visible to observers
- Codes can be shoulder-surfed
- Cheap safes are easily defeated
- Location matters
For secure storage guidance, see our spare key storage guide.
Being Present
The simplest alternative to giving keys:
- Be home for tradespeople
- Accompany cleaners on first visits
- Use delivery lockers instead of home delivery
Not always possible, but eliminates key distribution entirely.
Special Situations
Tenanted Properties
For landlords:
- Change locks between tenancies (non-negotiable)
- Use restricted key systems for tracking
- Document all key handovers
- Never assume tenants return all copies
Shared Households
For housemates:
- Agree on key distribution policy
- When one person leaves, consider lock change
- Keep records of who has copies
- Address lost keys. Understand the security risk of lost keys immediately
Care Situations
For those with carers:
- Minimise key holders
- Consider key safes with rotating codes
- Document all access providers
- Review when care arrangements change
When Keys Are Lost or Stolen
Assess the Risk
| Situation | Risk Level | Recommended Action |
|---|---|---|
| Lost away from home, anonymous | Lower | Monitor, consider change |
| Lost near home | Higher | Change locks |
| Lost with address attached | Critical | Immediate lock change |
| Stolen (opportunistic) | High | Change locks |
| Stolen (targeted) | Critical | Immediate lock change + police |
Immediate Actions
- Assess how identifiable the keys are
- Secure the property immediately if high risk
- Report if stolen (police reference for insurance)
- Change locks if risk warrants
For comprehensive lost key guidance, see what to do when keys are lost.
Take Action
Right now, can you list everyone who has a key to your home?
If not, key control has slipped. That’s normal—life is busy and keys distribute gradually over years. But recognising it is the first step.
Start a key holders list. Identify unnecessary distribution. Decide whether recovery is sufficient or whether a fresh start is warranted.
Your locks are only as secure as your control over who holds the keys.