The average cost to install a French door ranges from about $600 to just over $1,000, as of 2015. This is the total cost including installation, labor and the door itself, according to Homewyse.
Though the total estimated cost to install a French door covers most labor and installation costs, there are some costs not included in this figure. For instance, the cost does not include modifications that may be needed, repairs or relocation of existing structures. The price may also go up if electrical, ventilation or heating and air conditioning systems need to be brought up to compliance before the door is installed.
Other additional costs to install a French door may arise if using a general contractor. If a general contractor is overseeing the work of a subcontractor, there may be a markup in price for the service. Contractors who are bonded, insured and licensed are highly recommended, but also more expensive. In most cases, if a general contractor is supervising the project, a homeowner can expect to add between 11 and 19 percent more to the total cost. Sales tax on the supplies and materials may also add to the total cost of installation, as may any inspection or permit fees.