Rewiring the electrical lines in an entire home is a massive undertaking. It will involve the employment of an electrician as it is not something that a do-it-yourselfer should attempt. If you're trying to estimate how much rewiring your home will cost, break down the project into as much detail as possible and estimate the prices for each step.
Go through your home and count the number of electrical sockets in every room. Be precise and try to get the most accurate number possible. Also count all light fixtures, built-in devices that run on electrical power such as ceiling fans and devices like your thermostat. Typically, the service charge for each one of these electrical devices can range from £40 to £80. However, these are just average prices and the actual cost per device will vary depending on the electrician. These prices do not include materials.
Determine whether you have a "large home" or a "small home." A small home would be around 93 square metres (1,000 square feet) with only one floor, while a large home would be anything larger than 93 square metres (1,000 square feet) and with two or more floors. The average cost (which again will vary depending on your location) of the materials to rewire homes are between £195 and £650 for small homes and between £650 and £1,950 for a large home. These prices do not include labour.
Add the amount you estimated in Step 1 to the amount you estimated in Step 2. This will give you an estimated total cost to completely rewire your home.
Add £650 to £1,625 to the total you got in Step 3 if rewiring your home involves installing a completely new electrical panel. Add £520 to £650 (on average) if rewiring your home involves upgrading your existing electrical panel but not replacing it.