Glenfield, comprising the statistical areas of Glenfield West, Glenfield South West, Glenfield Central and Glenfield East, had a population of 13,539 at the 2018 New Zealand census, an increase of 1,176 people since the 2013 census, and an increase of 2,061 people since the 2006 census. There were 4,257 households. There were 6,708 males and 6,828 females, giving a sex ratio of 0.98 males per female, with 2,310 people aged under 15 years, 3,381 aged 15 to 29, 6,336 aged 30 to 64, and 1,515 aged 65 or older. Ethnicities were 44.5% European/Pākehā, 7.0% Māori, 4.8% Pacific peoples, 47.6% Asian, and 4.8% other ethnicities. The proportion of people born overseas was 54.2%, compared with 27.1% nationally. Although some people objected to giving their religion, 43.1% had no religion, 39.8% were Christian, and 12.4% had other religions. Of those at least 15 years old, 3,618 people had a bachelor or higher degree, and 1,251 people had no formal qualifications. The employment status of those at least 15 was that 6,012 people were employed full-time, 1,569 were part-time, and 426 were unemployed.
The district's first official name was Freemans after John Freeman, who established a post office bureau in his home on the corner of Glenfield and Kaipatiki Roads in 1888. It was commonly referred to as Mayfield because the white blossom of the manuka and kanuka trees reminded settlers of May springtime ‘back home’ in England. The existence of Mayfield in Canterbury meant that the name was never officially bestowed upon the area by the postal service. On 12 March 1912, the area was renamed Glenfield by the postal service. The name Mayfield lives on in Mayfield Road, a quiet side road several hundred metres north of the Glenfield shops. Prior to the opening of the Auckland Harbour Bridge in 1959, Glenfield primarily consisted of farmland. During the 1960s, as access to the area improved, many of the large farm properties were subdivided to provide space for residential development. On 9 December 1971, in response to fears about commercial sprawl down the length of Glenfield Rd, Glenfield Mall opened. It was among the earliest enclosed malls in the country. It featured a large aviary in the centre of the mall. In 2000, Glenfield Mall was completely redeveloped as Westfield Glenfield, but in 2015 reverted to its original name. From 1 November 2010, Glenfield became part of the Kaipatiki Local Board area in the new Auckland Council.
Amenities
, a privately owned hospital, is in Wairau Road.
Education
Glenfield College, founded in 1969, is a secondary school with a roll of students. Glenfield Intermediate, founded in 1972, is an intermediate school with students. Glenfield Primary School, founded in 1959, is a contributing primary school with a roll of. All three schools are coeducational. Rolls are as of The South Seas Film, Television, and Animation school is in Glenfield.