Riverdale is a suburb of Gisborne, in the Gisborne District of New Zealand's North Island.

Riverdale covers 2.10 km (0.81 sq mi) and had an estimated population of 2,740 as of June 2024, with a population density of 1,305 people per km.

Historical population

Year	Pop.	±% p.a.
2006	1,638	—
2013	2,178	+4.15%
2018	2,646	+3.97%
Source:

Riverdale had a population of 2,646 at the 2018 New Zealand census, an increase of 468 people (21.5%) since the 2013 census, and an increase of 1,008 people (61.5%) since the 2006 census. There were 1,002 households, comprising 1,188 males and 1,458 females, giving a sex ratio of 0.81 males per female, with 381 people (14.4%) aged under 15 years, 357 (13.5%) aged 15 to 29, 927 (35.0%) aged 30 to 64, and 984 (37.2%) aged 65 or older.

Ethnicities were 79.0% European/Pākehā, 27.4% Māori, 1.9% Pacific peoples, 2.8% Asian, and 1.2% other ethnicities. People may identify with more than one ethnicity.

The percentage of people born overseas was 10.3, compared with 27.1% nationally.

Although some people chose not to answer the census's question about religious affiliation, 39.1% had no religion, 49.9% were Christian, 1.6% had Māori religious beliefs, 0.7% were Hindu, 0.2% were Muslim, 0.2% were Buddhist and 1.0% had other religions.

Of those at least 15 years old, 303 (13.4%) people had a bachelor's or higher degree, and 612 (27.0%) people had no formal qualifications. 294 people (13.0%) earned over $70,000 compared to 17.2% nationally. The employment status of those at least 15 was that 837 (37.0%) people were employed full-time, 246 (10.9%) were part-time, and 42 (1.9%) were unemployed.

Individual statistical areas

Name	Area (km)	Population	Density (per km)	Households	Median age	Median income
Lytton	0.86	1,371	1,594	537	67.2 years	$23,700
Riverdale	1.24	1,275	1,028	465	43.0 years	$30,400
New Zealand					37.4 years	$31,800

Nelson Park is a sports ground, local park and dog walking area, located in Riverdale.

Lytton High School is a Year 9–13 coeducational state secondary school with a roll of 587. The school includes Te Whare Whai Hua Teenage Parent Centre, a co-educational public school for teenage parents.

Riverdale School is a year 1–6 coeducational state primary school with a roll of 133. The school was established in 1958. The school has hosted a regional chess tournament since 2006.

Te Kura Kaupapa Māori o Nga Uri A Maui is a Year 1–15 Māori immersion school with a roll of 215.

Sonrise Christian School is a Year 1–10 state integrated school with a roll of 134.

All these schools are co-educational. Rolls are as of August 2024.

The Eastern Institute of Technology has a rural campus in Riverdale. It is used for EIT courses and community-run horticulture and gardening classes.