In Collin County a service upgrade involves three parties: the electrician, the city's permit office and the delivery utility, which is Oncor or, in parts of the county, CoServ. A typical 100-amp to 200-amp replacement is estimated at $2,200–$4,800 all in. A 400-amp service is built on a 320-amp meter socket, which Oncor says is adequate for a 400-amp panel, and is quoted after a load calculation.
This guide is part of our Electrical Panel Upgrades service in Dallas–Fort Worth.
In Frisco, McKinney, Allen and Plano, a 200-amp or 400-amp service upgrade involves three parties: the electrician who builds the new service, the city that permits and inspects it, and the utility that delivers power, which is Oncor or, in parts of Collin County, CoServ. A typical 100-amp to 200-amp replacement is estimated at $2,200–$4,800 all in. A 400-amp service is quoted after an on-site load calculation. It is usually built on a 320-amp meter socket, which Oncor says is "adequate to serve a 400 ampere panel."
Is my address served by Oncor or CoServ?
Check the delivery charges on your electric bill: they name the company that owns the wires to your house. Collin County has more than one. CoServ says its electric service area "includes parts of Denton, Collin, Cooke, Grayson, Tarrant and Wise counties" (CoServ), and it will confirm in writing whether it serves an address. Frisco's resident guide lists both CoServ and Oncor's outage line under electricity. If no bill exists yet, our guide to which electric company serves your area walks through the other ways to find out.
It matters because the meter, the disconnect and the reconnect belong to the utility, and each utility has its own rules for them. Find out which one you have before the job is scheduled, not on the day.
What does Oncor require during a service upgrade?
Oncor's Electric Service Guidelines (February 2025) set the rules for its meters:
- "Only qualified electrical workers are permitted to remove meter seals and work inside meter enclosures."
- Before removing a self-contained meter, the electrician calls Oncor at 1.800.518.2374 with the job address, the work, whether it needs an electrical inspection, and the dates the meter will be pulled and replaced. Oncor then sends someone to inspect and reseal the meter.
- Electricians can also submit temporary disconnect and reconnect requests through Oncor's Electrician Connect portal.
- Removing an Oncor meter without that authorization results in a charge to the customer, under Oncor's tariff.
We pull the permit, request the disconnect and reconnect, build the new service to the utility's metering requirements and schedule the inspection. Whether the wires to the house or the transformer have to change for a bigger service is the utility's decision, and its timing is the biggest variable in how fast a 400-amp job finishes. On a CoServ address the same steps apply, under CoServ's own rules, and we confirm them with CoServ before the job is scheduled.
Why is a 400-amp service built on a 320-amp meter socket?
Because meters and panels are rated differently. Oncor's guidelines (Section 500.06.01) put it this way: "A 320 ampere meter socket has a continuous rating of 320 amperes and a maximum rating of 400 amperes. A 400 ampere panel has a maximum rating of 400 amperes and a continuous rating of 320 amperes." Oncor concludes that "a 320 ampere socket is adequate to serve a 400 ampere panel." So a quote for a "400-amp upgrade" that lists a 320-amp meter base is not short-changing you. Many residential 400-amp services are built as two 200-amp panels fed from that one meter base, which also adds breaker spaces.
Whether a house needs 400 amps is a load calculation question, not a square-footage one. The NEC's Article 220 calculation adds up lighting, receptacles, appliances, heating and cooling, applies the code's demand factors, and adds the new loads, such as EV chargers, a heat pump with electric backup heat, a pool or a shop. Most homes run fine on 200 amps. We cover the 400-amp decision, and the cheaper alternatives such as EV load management, in 200 to 400 amp service upgrades in DFW.
Permits in Frisco, McKinney, Allen and Plano
A service upgrade is permitted and inspected work, and the licensed electrical contractor pulls the permit. What each city publishes:
| City | What the city publishes |
|---|---|
| Frisco | Electrical contractors "must register with Building Inspections prior to permit issuance" (Frisco contractor registration) |
| Allen | Adopted codes sheet lists the National Electrical Code as "Per TDLR"; Building and Code Division, 214.509.4130 (Allen adopted codes) |
| Plano | Permits are issued through the city's Building Inspections department (Plano Building Inspections) |
| McKinney | Ask the city's Development Services department; we confirm before quoting |
TDLR adopted the 2026 NEC as the state electrical code effective September 1, 2026 (TDLR). Allen's sheet ties the city's electrical code to TDLR, and other cities adopt editions by ordinance on their own schedule, so we confirm the edition with the permit office before quoting. See which NEC applies in each DFW city.
A replaced service also brings a surge protector. NEC 230.67 requires a Type 1 or Type 2 surge-protective device for services supplying dwelling units, and "where service equipment is replaced, all of the requirements of this section shall apply" (Leviton, NEC 230.67). We include it in the quote. More in whole-home surge protector cost.
What does a service upgrade cost in Collin County?
A typical 100-amp to 200-amp panel replacement is estimated at $2,200–$4,800 all in, the same band we publish across Dallas-Fort Worth. A 400-amp service sits above that and is quoted after the load calculation. What moves either one:
- The meter base and service entrance: reused, or replaced with a larger one
- Overhead service with a mast, or underground service
- Grounding and bonding that has to be brought up to the current code
- Where the panel is, and whether it has to move
- One panel or two, and how many circuits have to be extended to reach them
- Whether the utility has to change anything on its side, which mostly affects the schedule
You get a written quote before any work starts. Financing is available through Synchrony Bank, subject to credit approval (financing options). See panel upgrades, or the Plano panel upgrade page. Our Frisco, McKinney, Allen and Plano pages cover the other work we do in each city.
Adding an EV, a heat pump or a pool in Collin County?
Load calculation first, then a written quote. Mon–Fri 7 AM to 7 PM. Licensed Texas Electrical Contractor TECL #40628.
Sources
Collin County service upgrade questions
Your electric bill names the delivery company. CoServ says its electric service area includes parts of Collin County and will confirm in writing whether it serves an address, and Frisco's resident guide lists both CoServ and Oncor. The answer decides whose rules apply to the meter, the disconnect and the reconnect.
Because meter sockets are rated by continuous current and panels by maximum current. Oncor's Electric Service Guidelines say a 320 ampere meter socket has a continuous rating of 320 amperes and a maximum of 400, the same capabilities as a 400 ampere panel, and that a 320 ampere socket is adequate to serve a 400 ampere panel.
A typical 100-amp to 200-amp replacement is estimated at $2,200–$4,800 all in. The meter base, service entrance, grounding and panel location decide where it lands, and the price is confirmed in writing after an on-site load calculation. A 400-amp service is quoted after that calculation.
The utility does the disconnect, the meter and the reconnect. On Oncor service, Oncor's guidelines require the electrician to call before pulling a meter, and electricians can request temporary disconnects and reconnects through Oncor's Electrician Connect portal. We request them as part of the job. On CoServ service, we follow CoServ's process.
Yes. A service upgrade is permitted and inspected work, and the licensed electrical contractor pulls the permit. Frisco, for example, requires electrical contractors to register with Building Inspections before a permit is issued. We confirm each city's process and code edition before quoting.
