Electrical Panel Upgrades: A Step-by-Step Guide for Electricians

A service upgrade is one of the most profitable jobs in residential electrical work — and one of the most scrutinized by inspectors. Get the sequence right and a 200A panel swap is a clean one-to-two day job. Here is the workflow experienced electricians follow.

1. Start with the load calculation

Before you quote anything, run a standard or optional method load calculation per NEC Article 220. This tells you whether the customer actually needs 200A, whether the existing service entrance conductors are adequate, and protects you if the inspector asks. Never size a panel by guessing.

2. Coordinate the disconnect with the utility

You cannot cut the meter seal and pull the meter on your own in most jurisdictions. Schedule the utility disconnect and reconnect in advance — this is the single biggest cause of blown timelines on panel jobs. Confirm whether they want an overhead or underground reconnect and who owns the weatherhead.

3. Plan the new panel layout before you kill power

Photograph the existing panel, label every circuit, and map your new breaker arrangement first. Group multi-wire branch circuits, plan AFCI/GFCI requirements by room, and leave spare spaces. A clean, logical panel is what separates a pro install from a callback magnet.

4. Bond and ground correctly

This is where most panel jobs fail inspection. At a service upgrade you must: bond the neutral to ground at the service disconnect only, separate neutrals and grounds in any downstream subpanel, drive or verify two ground rods (or a single rod tested under 25 ohms), and bond the water and gas piping. Get the grounding electrode system right and the rest is straightforward.

5. Torque to spec and document

Use a torque screwdriver on every lug and breaker — loose connections cause the overheating inspectors look for, and most panels now print torque values inside the door. Fill out the panel directory completely. Take photos of the grounding and bonding before you close it up.

6. Inspection-ready handoff

Leave the working clearances clear (30" wide, 36" deep, 78" high), label the service disconnect, and have your load calc on hand. A panel that's neat, correctly bonded, and documented passes the first time — and first-time passes are where the margin on these jobs lives.