Fernside is a small rural community in the Waimakariri District, New Zealand. In 1901, Fernside had (with its neighbourhood) a population of 550.^[3] As of the 2006 New Zealand census, Fernside has a population of 1491.^[4]

Fernside statistical area covers 39.03 km² (15.07 sq mi)^[1] and had an estimated population of 1,400 as of June 2023,^[2] with a population density of 36 people per km².

Before the 2023 census, the statistical area had a larger boundary, covering 41.48 km² (16.02 sq mi).^[1] Using that boundary, Fernside had a population of 1,326 at the 2018 New Zealand census, an increase of 102 people (8.3%) since the 2013 census, and an increase of 390 people (41.7%) since the 2006 census. There were 456 households, comprising 654 males and 672 females, giving a sex ratio of 0.97 males per female. The median age was 45.0 years (compared with 37.4 years nationally), with 258 people (19.5%) aged under 15 years, 204 (15.4%) aged 15 to 29, 666 (50.2%) aged 30 to 64, and 195 (14.7%) aged 65 or older.

Ethnicities were 95.2% European/Pākehā, 8.6% Māori, 0.5% Pasifika, 1.1% Asian, and 1.6% other ethnicities. People may identify with more than one ethnicity.

The percentage of people born overseas was 12.4, compared with 27.1% nationally.

Although some people chose not to answer the census's question about religious affiliation, 53.6% had no religion, 36.4% were Christian, 0.2% were Hindu and 1.1% had other religions.

Of those at least 15 years old, 186 (17.4%) people had a bachelor's or higher degree, and 165 (15.4%) people had no formal qualifications. The median income was $36,500, compared with $31,800 nationally. 255 people (23.9%) earned over $70,000 compared to 17.2% nationally. The employment status of those at least 15 was that 549 (51.4%) people were employed full-time, 228 (21.3%) were part-time, and 24 (2.2%) were unemployed.^[5]

Fernside School is Fernside's only school, and was established in 1864.^[6] It is a decile 10 state co-educational full primary, with 267 students (as of February 2024).^[7]

The average temperature in summer is 16.2, and in winter is 6.4.^[8]