The rates for each period are listed online no later than one month and one week after each filing period ends. See the table below for current due dates, or sign up for email alerts to receive quarterly updates and information, by going to the Tax.Colorado.gov/email-sign-up page and clicking on Sign Up for Multiple Lists.
| Period Ending: | ECMC Publishes rate by: | Return and Payment Due by: | Clean Transit Rate | Wildlife & Land Rate | Total Oil Rate (per Barrel) | Total Gas Rate (per MCF) | ||
|---|---|---|---|---|---|---|---|---|
| Oil | Gas | Oil | Gas | |||||
9/30/2025 | 11/08/2025 | 12/1/2025 | ||||||
12/31/2025 | 02/08/2026 | 03/02/2026 | ||||||
| 03/31/2026 | 05/08/2026 | 06/01/2026 | ||||||
6/30/2026 | 08/08/2026 | 08/31/2026 | ||||||