For mole exact calculation of combined heat transfer in the case of finned tube banks (e.g., in the convective section of a furnace), the radiative heat transfer cannot be neglected. A new method for relatively simple calculation of total heat flux (convection + radiation + conduction in fins) is fully compatible with that for bare tube banks/bundles developed earlier. It is based on the method of radiative coefficients. However, the resulting value of heat flux must be corrected due to fin thickness and especially due to the fin radiative influence. For this purpose the so-called multiplicator of heal flux was introduced. The applicability of this method has been demonstrated on a tubular fired heater convective section. A del eloped computer program based on the method has also been used for an analysis of the influence of selected parameters to shaw the share of radiation on the total heat flux.