Adults who go missing in Avon and Somerset and are deemed "low-risk" may not spark a police search for 36 hours.
The proposed change in approach comes as the force declares itself at tipping point after years of budget cuts and falling officer numbers.
Avon and Somerset Police said up to 30% of its resources was spent on missing people rather than on solving crimes.
The scheme is due to begin in April and will be reviewed by the force.
What is low-risk?
According to official police guidelines:
- A no-risk missing person (not used for children in Avon & Somerset) is where there is no risk of harm to either the subject or the public
- A low-risk missing person is where risk of harm is assessed as possible but minimal - for instance an adult who has had a family argument and storms off but has no history of self-harm/mental health issues
- A medium-risk missing person is where risk of harm is "likely but not serious", possibly a child who repeatedly goes missing or somebody with dementia who goes missing a lot
- A high-risk missing person is where harm to them or the public is very likely
The force calculates that it currently spends about £56,000 per day on searching for missing people, which it said could be reduced by using the proposed approach.
It is now considering who to actively search for as 40% of those who go missing disappear more than once.
Det Supt Richard Kelvey said: "We are at a point where we have to say to some families, 'call us in 12 hours' time'.
"If we didn't deal with missing people, we would probably have 300 more people on the ground."
- In 2017-2018 the force was alerted to about 8,000 missing people - about 26 a day
- Forty per cent of those who go missing are children
- About 4,500 people go missing more than once - for some it is 50 times in a year
- Seventy-five per cent of missing people are found within 24 hours, and many return of their own accord
- Many are adults in crisis or vulnerable children in care
The police force said when delaying the deployment of officers for low-risk cases, they reassured relatives and advised them to call back in 12 hours if they felt "the risk had changed".
Karen Robinson, from the charity Missing People UK, said: "Many children and adults are running away from harm, or become victims or crime while missing, so are in desperate need of support.
"It's vital that police have adequate resources to respond and investigate when someone disappears."
Mr Kelvey said: "We try to do the best job we possibly can, to find people and prevent them coming to harm.
"If there is a high risk missing person, we throw everything at it we really do."
Avon and Somerset Police Federation said the force had 700 fewer officers compared to 2010, and it blamed government cuts.
The Home Office has pledged an extra £161m this year for England and Wales' 43 police forces, which its says will protect police budgets in "real terms".
- This story was updated to clarify that Avon and Somerset Police's proposed change in approach to missing people applies to low-risk missing adults and will begin in April.