| Official Name: | Errezil |
| Pushpin Map: | Spain |
| Pushpin Map Caption: | Location in Spain. |
| Subdivision Type: | Country |
| Subdivision Name: | Spain |
| Subdivision Type1: | Autonomous community |
| Subdivision Name1: | Gipuzkoa |
| Subdivision Type2: | Province |
| Area Total Km2: | 32.46 |
| Elevation M: | 304 |
| Population Density Km2: | auto |
| Timezone: | CET |
| Utc Offset: | +1 |
| Timezone Dst: | CEST |
| Utc Offset Dst: | +2 |
| Website: | www.errezil.eus |
Errezil (Spanish; Castilian: Régil) is a town in the province of Gipuzkoa in the autonomous community of Basque Country, located in the north of Spain. According to the 2016 Basque sociological survey, Errezil has the largest percentage of Basque language speakers of any municipality in the Basque Country, with over 90% of Errezil respondents reporting Basque as their first language and/or reporting speaking Basque at home.