Estimating non-volatile Particulate Matter (nvPM) - or black carbon - emissions during an aircraft mission is extremely challenging, because of the lack of reliable data in flight. For this reason, a detailed study has been undertaken to estimate in-flight emissions from data measured on the ground during engine certification. Aircraft engine emissions certification is based on the "Landing and Take-Off" (LTO) cycle. The aim of this regulation is to control emissions in the vicinity of the airport (below 3000ft). New certification standards on nvPM have been introduced recently. With these regulations, manufacturers are now reporting nvPM emissions data publicly. All emissions data of in-production engines are available in the engine emissions data bank (EEDB), downloadable from the European Union Aviation Safety Agency (EASA) website. Methodologies have been proposed to estimate emissions at altitude and calculate total mission emissions for NOx, which are only relying on these publicly available data from the EEDB. In the following, a new methodology for estimating nvPM emissions at altitude is proposed. The methodology was developed and validated in the framework of the CAEP technical working groups. It comprises four dedicated steps. In the present article, the different steps are explained and validation data is provided as applicable. Examples of in-production engines are analyzed, discussed, and compared against the full methodology using proprietary engine performance and emissions certification data. Following the proposed methodology, total nvPM mass and number mission emissions can be estimated and used for emissions inventories and evaluation of climate impacts.