Between July and August last year a third of all homes burgled in Humberside had been left insecure, with their doors or windows left open.
There were 180 incidents reported over the two months.
The latest figures available from Humberside Police show that there were 58 sneak-in burglary offences in Hull, East Yorkshire, North East Lincolnshire and North Lincolnshire.
Detective Chief Inspector Paul Kirby said: “Being a victim of burglary is deeply upsetting for the victims and their family.
“We want to see less offences this year, but need the public to assist us by stopping sneak-in burglars who target properties with open doors or windows.
“In vast majority of cases the offenders are opportunists walking around residential area’s looking for possible insecure properties.
“I would therefore urge people to make sure that they always lock doors - whether they are in or not and day or night - and only keep doors or windows open in occupied rooms.
“Unfortunately, insecurities are like an open invitation for opportunist sneak-in burglars who only need a few seconds to grab property from your home.
“As a force we do everything possible to tackle the threat of these opportunist offenders with intelligence led targeted police patrolling, crime prevention and education activity in the community and disruption work with prolific offenders.
“However all this good work can be undone if people allow offenders into their home via open doors or windows -so please keep your home secure and keep the sneak thief out.”
Police chiefs want residents to register details of their electrical items and valuables on the national immobilise.com database, which police forces use to try to identify the rightful owners of stolen goods recovered by officers.
They also want people to remain vigilant and report anyone they see acting suspiciously.
Call Humberside Police on 101.