National Grid (Massachusetts) time-of-use & off-peak hours

On G-3, on-peak hours run 8 AM – 9 PM on weekdays. Below is every active TOU rate plan we track for National Grid (Massachusetts) — 2 plans — with period boundaries verified against the published tariff. No price values; periods only.

For developers & agents

Query National Grid (Massachusetts) periods programmatically.

One call returns the current period and the next transition time for any U.S. ZIP or address — GET /query/current over REST, or the same data through MCP for AI agents.

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Rate plan schedules

Every active time-of-use plan we track for National Grid (Massachusetts), with its period boundaries.

G-3 General Service Time-of-Use Commercial
PeriodSeasonDaysHours
On-Peak All year Mon–Fri 8 AM – 9 PM
Effective
Mar 31, 2025
Verified
OPCR Off-Peak Charging Rebate EV
PeriodSeasonDaysHours
On-Peak All year Every day 1 PM – 9 PM
Effective
Nov 1, 2025
Verified

Frequently asked

  1. What are National Grid (Massachusetts)'s on-peak hours?

    On the G-3 plan (General Service Time-of-Use), on-peak hours run from 8 AM – 9 PM on weekdays. All remaining hours are classified as off-peak.

  2. Does National Grid (Massachusetts) charge more for electricity at certain times?

    Yes. National Grid (Massachusetts) 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 2 active schedules; tou.tools does not publish pricing ($/kWh) details.

  3. How do I get National Grid (Massachusetts) 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 National Grid (Massachusetts) 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 National Grid (Massachusetts)'s plans?

    For customers on EV-specific plans like OPCR, 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.