There were no Jacindas or Judith's on the top 10 list for 2020 and no increase in Ashley's despite these names appearing often in the media over the past 12 months.
A total of 17,749 different first names were given to 58,676 babies born in 2020.
In 2019, there were 18,816 different first names given to 61,018 babies.
Isla first made the top 100 girls' names in 2004, and 2020 is the first year it has topped the list.
Charlotte keeps the second spot while Amelia is now the third most popular name.
Jack is the second most popular name for boys and Noah the third.
Nikau and Mia remained the most popular Māori boys' and girls' names last year, having topped the list for the past several years.
Department of Internal Affairs registrar-general births, deaths and marriages Jeff Montgomery said registering a baby is important step as it ensures your child has an official identity and can access their legal rights as they grow up.
The full list of top baby names is available on SmartStart, an online tool for new parents.
Top 10 overall
Girl names
1. Isla - 243
2. Charlotte - 222
3. Amelia - 213
4. Olivia - 208
5. Willow - 184
6. Harper - 177
7. Ava - 175
7. Lily - 175
9. Sophie - 168
10. Ella - 163
Boy names
1. Oliver - 315
2. Jack - 261
3. Noah - 240
4. Leo - 235
5. Lucas - 206
6. George - 197
7. Charlie - 183
8. William - 175
8. Thomas - 175
10. Hunter - 174
Top Māori names
Girl - Kōtiro
1. Mia - 162
2. Aria - 132
3. Maia - 85
4. Amaia - 59
5. Kora - 40
6. Kaia - 34
7. Aroha - 33
8. Anahera - 32
9. Tiana - 20
10. Kaea - 18
Boy - Tama
1. Nikau - 63
2. Manaia - 51
3. Ari - 49
4. Mikaere - 37
5. Koa - 31
6. Ihaia - 29
6. Manaaki - 29
8. Te Ariki - 27
9. Taika - 25
10. Mateo - 24
10. Wiremu - 24
