| Kostopil Raion | |
| Native Name: | Костопільський район |
| Native Name Lang: | uk |
| Settlement Type: | Raion |
| Flag Alt: | Flag of Kostopil Raion |
| Shield Alt: | Coat of arms of Kostopil Raion |
| Coordinates: | 50.9306°N 26.3144°W |
| Subdivision Type: | Country |
| Subdivision Type1: | Region |
| Subdivision Name1: | Rivne Oblast |
| Parts Type: | Subdivisions |
| Parts Style: | coll |
| P1: | — city councils |
| P2: | — settlement councils |
| P3: | — rural councils |
| P4: | Number of localities: — cities |
| P5: | |
| P6: | 61 — villages |
| P7: | — rural settlements |
| Established Title1: | Established |
| Established Date1: | 1939 |
| Established Title2: | Disestablished |
| Established Date2: | 18 July 2020 |
| Seat Type: | Admin. center |
| Seat: | Kostopil |
| Leader Title: | Governor |
| Leader Title1: | Chairman |
| Unit Pref: | Metric |
| Area Total Km2: | 1496 |
| Population Total: | 63462 |
| Population As Of: | 2020 |
| Population Density Km2: | auto |
| Timezone1: | EET |
| Utc Offset1: | +02:00 |
| Timezone1 Dst: | EEST |
| Utc Offset1 Dst: | +03:00 |
| Postal Code Type: | Postal index |
| Area Code Type: | Area code |
| Area Code: | +380 |
| Website: | http://www.rv.gov.ua/sitenew/kostopilsk Kostopil Raion |
Kostopil Raion (Ukrainian: Костопільський район) was a raion in Rivne Oblast in western Ukraine. Its administrative center was the town of Kostopil. The raion was abolished and its territory was merged into Rivne Raion on 18 July 2020 as part of the administrative reform of Ukraine, which reduced the number of raions of Rivne Oblast to four.[1] [2] The last estimate of the raion population was