According to the inquiry method, the installation fee belongs to the construction service tax classification code. Equipment installation costs refer to all costs incurred during the construction of equipment to be installed, including direct costs, construction management fees and other indirect costs. The direct cost of equipment installation project consists of labor cost, material cost, construction machinery use fee and other direct costs. Labor cost refers to the wages of workers directly engaged in equipment installation.

Legal basis: Article 32 of the Law of People's Republic of China (PRC) on the Administration of Tax Collection, if a taxpayer fails to pay the tax within the prescribed time limit and a withholding agent fails to pay the tax within the prescribed time limit, the tax authorities shall order him to pay the tax within the prescribed time limit, and impose a late fee of 0.5% of the overdue tax on a daily basis from the date of tax payment.