Emergency service teams were called in to find the missing 82-year-old man, who had last been seen in Eastney at 4.30pm yesterday wearing just shorts and slippers.
Hampshire police was the first organisation scrambled, responding at 7.05pm last night to begin the hunt, with patrol officers searching across the city.
However, other agencies were soon called upon as concerns over the 82-year-old’s health mounts.
Drones and helicopters were also used, with searches focusing on the Southsea and Eastney areas of the city for almost four hours.
Efforts were stood down at about 7.15am, the UK Coastguard said, after the missing pensioner was found safe and well.
A spokeswoman from Hampshire police added: ‘An 82-year-old man from Portsmouth was located in the Fratton area at approximately 7am this morning.’