UniSource Energy Services peak
& off-peak hours

Below is every active TOU rate plan we track for UniSource Energy Services — 12 plans — with period boundaries verified against the published tariff. No price values; periods only.

Rate Plans

ERRDTT Residential Demand Time-of-Use Tech (R-Tech) [pilot]

Residential
PeriodDaysHours
May 1 – Sep 30
On-Peak Mon–Fri 3 PM – 7 PM
Oct 1 – Apr 30
On-Peak Mon–Fri 6 AM – 9 AM
On-Peak Mon–Fri 6 PM – 9 PM
Effective
Feb 1, 2024
Verified

ERRESDT Residential Demand Time-of-Use

Residential
PeriodDaysHours
May 1 – Oct 31
On-Peak Mon–Fri 3 PM – 7 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 6 AM – 9 AM
On-Peak Mon–Fri 6 PM – 9 PM
Effective
Feb 1, 2024
Verified

ERREST Residential Service Time-of-Use

Residential
PeriodDaysHours
May 1 – Oct 31
On-Peak Mon–Fri 3 PM – 7 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 6 AM – 9 AM
On-Peak Mon–Fri 6 PM – 9 PM
Effective
Feb 1, 2024
Verified

EGLGSST Large General Service Schools Time-of-Use

Commercial
PeriodDaysHours
May 1 – Oct 31
On-Peak Mon–Fri 3 PM – 7 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 5 AM – 9 AM
On-Peak Mon–Fri 5 PM – 9 PM
Effective
Feb 1, 2024
Verified

EGLGST Large General Service Time-of-Use

Commercial
PeriodDaysHours
May 1 – Oct 31
On-Peak Mon–Fri 2 PM – 8 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 5 AM – 9 AM
On-Peak Mon–Fri 5 PM – 9 PM
Effective
Feb 1, 2024
Verified

EGMGSST Medium General Service Schools Time-of-Use

Commercial
PeriodDaysHours
May 1 – Oct 31
On-Peak Mon–Fri 3 PM – 7 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 5 AM – 9 AM
On-Peak Mon–Fri 5 PM – 9 PM
Effective
Feb 1, 2024
Verified

EGMGST Medium General Service Time-of-Use

Commercial
PeriodDaysHours
May 1 – Oct 31
On-Peak Mon–Fri 2 PM – 8 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 5 AM – 9 AM
On-Peak Mon–Fri 5 PM – 9 PM
Effective
Feb 1, 2024
Verified

EGSGSDT Small General Service Demand Time-of-Use

Commercial
PeriodDaysHours
May 1 – Oct 31
On-Peak Mon–Fri 2 PM – 8 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 5 AM – 9 AM
On-Peak Mon–Fri 5 PM – 9 PM
Effective
Feb 1, 2024
Verified

EGSGST Small General Service Time-of-Use

Commercial
PeriodDaysHours
May 1 – Oct 31
On-Peak Mon–Fri 2 PM – 8 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 5 AM – 9 AM
On-Peak Mon–Fri 5 PM – 9 PM
Effective
Feb 1, 2024
Verified

EGDCFCX Stand-Alone Electric Vehicle Charging (DCFCX)

EV
PeriodDaysHours
All year
Super Off-Peak Every day 10 PM – 4 AM
May 1 – Oct 31
On-Peak Mon–Fri 2 PM – 8 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 5 AM – 9 AM
On-Peak Mon–Fri 5 PM – 9 PM
Effective
Feb 1, 2024
Verified

ERDSOTE Residential Demand Super Off-Peak Time-of-Use Electric Vehicle

EV
PeriodDaysHours
All year
Super Off-Peak Every day 10 PM – 5 AM
May 1 – Oct 31
On-Peak Mon–Fri 3 PM – 7 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 6 AM – 9 AM
On-Peak Mon–Fri 6 PM – 9 PM
Effective
Feb 1, 2024
Verified

ERSOTE Residential Super Off-Peak Time-of-Use Electric Vehicle

EV
PeriodDaysHours
All year
Super Off-Peak Every day 10 PM – 5 AM
May 1 – Oct 31
On-Peak Mon–Fri 3 PM – 7 PM
Nov 1 – Apr 30
On-Peak Mon–Fri 6 AM – 9 AM
On-Peak Mon–Fri 6 PM – 9 PM
Effective
Feb 1, 2024
Verified
Free · no credit card

Use these UniSource Energy Services hours in your app.

Current period and next transition for any ZIP or address.

Get a free API key

500 calls/mo · REST & MCP

or read the docs

FAQ's

  1. What are UniSource Energy Services's on-peak hours?

    On the ERRDTT plan (Residential Demand Time-of-Use Tech (R-Tech) [pilot]), on-peak hours run from 3 PM – 7 PM and 6 AM – 9 AM and 6 PM – 9 PM on weekdays. All remaining hours are classified as off-peak.

  2. Does UniSource Energy Services charge more for electricity at certain times?

    Yes. UniSource Energy Services offers time-of-use (TOU) rate plans where electricity costs vary depending on the period. The period—peak, off-peak, mid-peak, or super off-peak—depends on the time, day, and season. This page lists boundaries for 12 active schedules; tou.tools does not publish pricing ($/kWh) details.

  3. How do I get UniSource Energy Services time-of-use periods in my app?

    Schedules are accessible programmatically via the tou.tools REST API and MCP server for AI agents. By querying a U.S. address or ZIP code, your application can instantly retrieve the current period and next scheduled transition time. Developer API keys are free.

  4. Do UniSource Energy Services time-of-use hours change during holidays or seasons?

    Yes. Peak hours and rate periods can vary by season (typically summer and winter halves) and special holidays. While some schedules like E-ELEC keep stable hours year-round, others introduce super off-peak windows or adjust peak times. Check each rate plan card above for specific seasonal boundaries.

  5. What is the best time to charge an EV under UniSource Energy Services's plans?

    For customers on EV-specific plans like EGDCFCX, ERDSOTE, ERSOTE, the most cost-effective time to charge is during super off-peak or off-peak hours. Charging during these designated windows significantly reduces electricity costs and minimizes demand on the grid.