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Are free-nights electricity plans worth it?
Free-nights plans charge nothing for electricity used between roughly 9 PM and 6 AM — but make up the cost through a higher rate during the remaining hours. Whether you come out ahead depends on how much of your usage actually falls in the free window. Published Sep 14, 2026.
By WattPal Editorial Team · Break-even estimates, not a bill guarantee.
How free-nights pricing works
A free-nights plan sets the retailer's energy charge to zero during the free window — typically starting between 8 PM and 11 PM through 6 AM (7 to 10 hours) — and charges a higher rate for the remaining paid hours. TDU delivery charges (Oncor, CenterPoint, etc.) still apply to every kWh, including night hours. The plan's Electricity Facts Label benchmarks at 1,000 kWh, assuming 35 % of that usage falls in the free window.
Want to see live rates in your area? Use the Plan Simulator to compare how flat and free-nights plans price your usage range side-by-side.
Break-Even Plan Visualizer
Compares retailer energy charges from each plan's EFL. TDU delivery is excluded since it applies equally to both.
Check the "Price components" section of your EFL document. Enter the "Energy Charge" for flat plans, and the "Daytime Energy Charge" plus "Base Charge" for free-nights plans. Avoid using the top 1,000-kWh average rate, which already bakes in statutory assumptions and TDU delivery charges.
Total electricity used
Share of power in free window
At 1,000 kWh: Flat Plan is $70.00 vs Free-Nights is $64.90.
The 35 % fraction assumption — and why it matters
Texas EFLs for free-nights plans are required by the PUCT electricity disclosure rule (§25.475) to benchmark at 1,000 kWh using a standard usage profile. The dominant residential assumption is that roughly 35 % of monthly usage occurs during the free window (roughly 9 PM–6 AM), leaving 65 % in paid hours.
This fraction is a regulatory benchmarking assumption, not a measurement of your home. Most Texas households use more than 35 % of their electricity during daytime hours because of air conditioning loads — meaning the calculator above may underestimate your free-nights plan cost. The actual share of your usage that falls in the free window can only be determined from 15-minute interval data.
Night-heavy user
EV charging, pool pump, and appliances scheduled after 9 PM. Night fraction may exceed 35 %; plan likely favorable.
Average household
A/C drives most of the summer load during the hottest afternoon hours. Night fraction often below 35 %; flat plan may win.
Day-shifted household
Home office, daytime appliances, or solar export during the day pushes free-nights plans to their worst case.
What this calculator does not include
The break-even calculator compares energy charges only at the assumed 35 % night fraction. It does not calculate:
- • TDU delivery charges (fixed and per-kWh), which apply regardless of plan type and add to total cost.
- • Recurring fees, enrollment fees, or early-termination fees.
- • Bill credits with usage thresholds that may or may not apply each month.
- • Seasonal variation — summer A/C loads shift more usage to daytime and make free-nights plans less favorable.
- • Free-window hours that differ from the assumed 9 PM–6 AM — always confirm the exact hours from the plan's EFL.
The bill-credit traps guide covers a related pricing pattern where credits disappear depending on usage thresholds.
Methodology and limitations
The break-even calculator uses the EFL standard night-fraction assumption of 35 % (free window 23:00–06:00, as documented in WattPal's methodology). Night kWh = usage × 0.35; day kWh = usage × 0.65. The free-nights plan cost equals (day kWh × paid rate) + base charge. The flat plan cost equals total kWh × flat rate. Both are energy-only estimates and exclude delivery charges and fees.
The break-even monthly usage is where the two plan costs are equal: base charge / (flat rate − paid rate × 0.65), expressed in kWh. All arithmetic is performed in the browser using IEEE 754 floating-point. Results are rounded to two decimal places for display. No usage data is sent to WattPal servers.
WattPal's personalized analysis applies a measured interval split from your SmartMeter Texas 15-minute data rather than the assumed fraction. It also applies validated delivery charges, fees, and EFL-parsed bill-credit conditions. The PUCT §25.475 disclosure rule governs the EFL format. Confirm free-window hours, rates, and fees from the specific plan's EFL before enrolling.
See your actual free-nights split
Upload your SmartMeter Texas CSV and WattPal will split your 15-minute interval usage into free and paid hours against the specific plan terms, apply validated delivery charges, and compare all eligible plans side-by-side.
Read the EFL guide, explore the plan simulator, or visit the Guides hub.