Dorset and Wiltshire Fire and Rescue Service is warning residents about scam emails linked to home fire safety visits.
The emails claim households could be charged £500 if they do not have a working smoke alarm.
The fire service says its official home fire safety visits are always free, and any smoke alarms fitted during visits are also provided at no cost.
Area Manager Marc House said any message suggesting people will be charged is a scam.
Residents are being urged not to click links or provide personal details in suspicious emails.
Suspected scam emails can be reported to the National Cyber Security Centre.
