100 to 200 Amp Service Upgrade: When Wyoming Homes Need It and What It Costs

Most Cheyenne homes built before 1985 came from the builder with 100 amp electrical service, which was generous for the era when central air conditioning was rare, kitchen appliances were modest, and the only large electric load was the dryer. In 2026, that same 100 amp service has to handle modern HVAC, induction ranges, EV chargers, hot tubs, finished basements with home theaters, and home offices with multiple computers. For many Cheyenne homeowners, an electrical service upgrade from 100 to 200 amp is the unlock that makes every other home improvement possible. Here is what the upgrade involves, when you need it, and what it costs in Wyoming in 2026.

Signs Your Home Needs a 200 Amp Service Upgrade

Several conditions indicate that your existing 100 amp service has reached its limit. Frequent main breaker trips when running multiple major appliances simultaneously is the clearest signal that aggregate load exceeds service capacity. Dim or flickering lights when the AC compressor or dryer kicks on indicates voltage sag from undersized service or an overloaded panel. No room for new circuits in your existing panel forces you to either subpanel (which still draws from the original 100 amp service) or upgrade. Planning to install any combination of EV charger, hot tub, electric range, or central air on a 100 amp service almost always requires upgrading first to safely accommodate the new load.

The Cheyenne building code calculation for service sizing factors in square footage, fixed appliances, and largest motor load. A 1,800 sq ft home with a 4-ton AC, electric dryer, electric range, and a planned Level 2 EV charger typically calculates to a required service size of 175 to 200 amps. Anything less than 200 amp service in this scenario will trip the main breaker under combined load, even if no individual circuit is overloaded.

What the Upgrade Actually Involves

A 100 to 200 amp service upgrade involves more than just swapping the panel. The full scope includes: replacing the meter base (the existing 100 amp meter base is rated only for 100 amp service), upgrading the service entrance conductors (the wires from the utility connection to the meter to the panel) to 4/0 aluminum or 2/0 copper, replacing or evaluating the service mast and weatherhead on overhead services, replacing the panel itself with a 200 amp main breaker panel, replacing or evaluating the grounding electrode system (ground rod and water-pipe bond), and pulling permits and coordinating the inspection plus the temporary utility disconnect with Black Hills Energy.

The temporary utility disconnect is what most homeowners do not anticipate. Black Hills Energy must physically pull the meter so the electrician can work on the meter base and service entrance, then reset the meter after passing inspection. This typically requires a 4 to 8 hour power outage during the upgrade, scheduled in advance with the utility. Your home will be without power for that window. We schedule outages for cool-weather days when freezer temperature is forgiving and provide a generator if you need one during the work.

2026 Cost Breakdown for Cheyenne

The full installed cost of a 100 to 200 amp service upgrade in Cheyenne in 2026 is a mid four-figure job, with the median residential project landing in the middle of that range. The cost components are: the new panel and 200 amp main breaker (Square D QO and Eaton CH are the premium choices), the new meter base, the service entrance conductors (priced by length), labor for an 8 to 12 hour two-electrician install, permit fees in Cheyenne and Laramie County, and any service mast replacement or gas-meter relocation work if needed.

Several factors push the cost higher. Underground service entrance (instead of overhead) adds a line because the underground conductors require trenching or pulling through existing conduit. Detached garages or outbuildings with subpanels need their feeder evaluated and possibly upgraded. Older homes with cloth-insulated wiring discovered during the upgrade may need a separate evaluation. Federal Pacific or Zinsco panels being replaced at the same time as the upgrade typically save 10 to 20 percent vs. doing the panel swap as a separate project later because labor and permit overlap.

Permitting and Inspection in Wyoming

Cheyenne and Laramie County both require permits for service upgrades, with a single inspection by the local jurisdiction (Cheyenne city or Laramie County depending on address). The permit application requires the panel and service entrance specs, an electrical contractor license number, and the homeowner’s name. Inspection happens after the new service is installed but before the utility resets the meter. A passing inspection releases the utility to reset the meter and restore power. Inspection failures (loose terminations, incorrect grounding, undersized conductors) typically require a small re-inspection fee plus the labor to fix the issue.

Skipping the permit creates two serious problems. First, your homeowner’s insurance can deny claims related to electrical fires if unpermitted electrical work is discovered as the cause. Second, when you sell the home, the buyer’s home inspector will flag the unpermitted panel work, which usually leads to either a price reduction or a requirement to retroactively permit and inspect. The retroactive process costs more than the original permit and creates closing delays.

Timeline from Quote to Power Restoration

A standard 100 to 200 amp service upgrade in Cheyenne typically takes 2 to 4 weeks from initial quote to final inspection. The timeline is: site visit and written quote (1 to 3 days), permit application and approval (3 to 7 business days in Cheyenne, longer in Laramie County), parts ordering for the panel and meter base (1 to 5 days for stocked items, longer for premium brands or higher-amp configurations), Black Hills Energy outage scheduling (usually 5 to 10 business days lead time), the install itself (one full day), and inspection plus utility reconnect (same-day or next-day depending on inspector availability).

Moonlight Electric Solutions handles every step of the service upgrade process across Cheyenne, Laramie, and Northern Colorado, including utility coordination, permit pulling, and same-day inspection scheduling when possible. Call (307) 757-5553 or request a free service upgrade quote and we will evaluate your existing service, calculate your home’s required size, and provide a complete installed price with no surprises.

Frequently Asked Questions

Will I lose power during a service upgrade?

Yes, for one scheduled window of 4 to 8 hours while the meter is pulled and the new service goes in. We schedule for cool-weather days when the freezer is forgiving and can provide a generator for the work window if you need one.

Can I just add a subpanel instead of upgrading?

A subpanel adds breaker slots but still draws from the same 100-amp service, so it does not fix a capacity problem. If the load calculation says you are at the limit, the upgrade comes first. Call (307) 757-5553 and we will run the numbers.

How long does the whole process take?

Typically 2 to 4 weeks: site visit and written quote, permit approval, parts, Black Hills Energy outage scheduling, one full install day, then inspection and reconnect. Contact us to start, or see completed upgrades in the gallery.

Read more on our service upgrades page, see our project gallery, or learn about the team.